ABB REF542 + RELAY Inclds Typ Connections

REF542plus Multifunction Protection and Switchgear Control Unit

1 DESCRIPTION

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2 CONFIGURATION

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3 FUNCTIONS

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4 APPLICATION EXAMPLES

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5 CONSTRUCTION

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6 TECHNICAL DATA

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7 CONNECTIONS

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8 INFORMATION

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IndustrialIT REF542plus has been tested and certified as IndustrialIT Enabled, Level 1 - connectivity. All product information is supplied in interactive electronic format, compatible with ABB Aspect ObjectTM technology. The IndustrialIT commitment from ABB ensures that every enterprise building block is equipped with the integral tools necessary to install, operate, and maintain efficiently throughout the product lifecycle. REF542plus belongs to the ProtectIT suite. Detailed information on IndustrialIT is available at .

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1 DESCRIPTION

Introduction

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The REF542plus Base unit

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The REF542plus HMI

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DESCRIPTION

Introduction REF542plus integrates in a single unit all the secondary functions for a medium voltage switchgear: • Protection; • Control; • Measurement; • Monitoring and self-diagnosis; • Communication. A medium voltage switchgear equipped with REF542plus becomes a complete, efficient and effective system for power distribution and management. The unit can be used indifferently in solidly earthed, low-resistance, compensated or unearthed networks; with radial, multifeeders or loop topology. The wealth of available protection functions makes the unit suitable for any kind of applications. Time-overcurrent either with definite or inverse time, directional time-overcurrent protections are implemented. Also the distance protection for overhead lines can be instantiated in the REF542plus. Motor protection functions include starting supervision, number of starts counting, locked rotor, thermal supervision, under power, reverse power and unbalanced load. ATEX certified versions for explosive environment, according to the directive 94/9/EC, are available. Large power transformers can be protected, among others, with the differential and the restricted earth fault protections. Power quality features such as power factor controller with resonance protection are available. For demanding applications, a REF542plus based system including a SUE 3000 unit, grants fast transfer switch between two incoming feeders in less than 30 ms.

Under voltage and over voltage protections, synchrocheck and frequency protection complete the set of protection functions for bus tie panels, incoming feeders and whenever needed. Time synchronization with an external master clock makes the fault-recording feature and events stamping with accuracy better than 1 ms. Four different communications protocols and an embedded WEB server open the REF542plus to any control system architecture. All these features are complemented with exceptional automation functions capabilities. Automatic transfer switch, motor restarts and reacceleration, load shedding, any kind of user defined automation sequence can be easily implemented inside the unit. The presence of a CAN Open standard interface allows connectivity to the huge market of CAN standard products such as terminal blocks and intelligent IO modules. The automation possibilities become almost unlimited. The following pictures show REF542plus installation examples in several switchgear.

REF542plus installed in air-insulated switchgear (AIS).

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The REF542plus is composed of two parts, a Base Unit and a Local Detached Human Machine Interface (LD HMI). The two parts are connected with a serial cable. The Base Unit contains the power supply, the main module, the analog and binary input and output (I/ O) modules. Optional modules can be inserted for supplementary functions. The HMI is an easy-to-use unit for the switchgear local control. The HMI is equipped with its own power supply. It can be installed on the low voltage compartment door or in a dedicated compartment close to the Base Unit. The HMI is used to locally operate the primary objects in the switchgear, to set the protection parameters, to visualize events and measurements. The separation between HMI and Base Unit grants several advantages and an overall increased flexibility: • Blind Base Units (without HMI) are possible; • One single HMI for several Base Units; • Easier HMI integration in the most convenient place; • Simplified Base Unit integration in the low voltage cubicle.

REF542plus installed in gas-insulated switchgear (GIS).

REF542plus Base Unit and HMI. 5

DESCRIPTION

The following figure shows an installation of the Base Unit and of the HMI in the low voltage compartment of the switchgear.

Base Unit mounting in the low voltage compartment and the HMI on the door.

The REF542plus Base Unit

Base Unit without connector plate and with extracted boards.

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The REF542plus Base unit is based on a realtime, multiprocessor architecture. A Digital Signal Processor (DSP) executes the protection functions, while a Microcontroller (MC) executes the control functions. Another processor on the optional communication module manages the communication with the station automation system. This separation guarantees higher reliability. A block diagram of the REF542plus is shown in the figure. The main module is equipped with the DSP and the MC. The CAN Open interface, the Ethernet interface for the embedded WEB server, the optical input port for time synchronization are located on the main module as well. The optional communication module takes care of the communication with the substation automation system.

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The binary inputs and outputs modules interface the primary process to send commands and to acquire status information. The analog input module acquires the current and voltage signals, both from instrument transformers or noninductive sensors. The optional analog 0/4 ... 20 mA output module and analog 4 ... 20 mA input module allow exchanging information with the 4... 20 mA or 0... 20 mA current loop.

Analog Output 0/4 ... 20 mA Module

Analog Input 4 ... 20 mA Module

Communication Module

Analog Input Module

Main Module

Binary Input Output Module (s)

REF542plus Base Unit block diagram.

The REF542plus HMI The HMI features a back-illuminated Liquid Crystal Display (LCD), 8 push buttons, several leds and an electronic key sensor. The language of the display can be selected among those available via the Operating Tool. The left half of the LCD provides a graphical representation of the primary objects controlled by the REF542plus in the switchgear. The right half of the LCD is for plain text visualization such as measurements and protection events. The LCD backlight is switched off automatically after 20 minutes of inactivity. The HMI is a complete system for the switchgear local management. The HMI allows the operator to set the protection functions, operate the primary objects, visualize measurements and events, reset alarms and change the unit working mode.

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Unit Ready. This green led is turned on when the unit is in the operational state. This led is switched off when the power supply is not present or when the unit is not operational.

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The HMI includes:

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Network communication Alarm Interlocking error 8x4 pages user programmable Leds Measurements bars PC interface Menu navigation

7 8 Object control: Open - Close - Select 9 Electronic keys sensor 10 Text 11 SLD view 12 Circuit-breaker fast opening 13 Unit ready

REF542plus HMI. 7

1 DESCRIPTION

Network Communication. This led is meaningful only when the REF542plus is equipped with a communication module and configured to use it. When a communication module is detected inside the unit, the led turns on to green. If a communication module is not detected or fails, the led turns from green to red. When the unit is not configured for the communication, this led is switched off. Alarm. This led turns to red when user defined alarms become true. Several arbitrary alarm conditions can be defined and configured with the operating tool. Alarm conditions could be the trip of a protection function, loss of SF6 in the circuit breaker, etc. When this led is on, it is not possible to close the circuit breaker or to download a new configuration. The alarm condition has to be removed and the alarm must be acknowledged first. Interlocking Error. This led is usually green. The led turns temporarily to red when the user attempts an operation that would violate the programmed interlocking conditions; for example switching a disconnector with the circuit breaker in closed position. Electronic Keys Sensor. This is the sensor for recognizing the electronic keys. Two different electronic keys are provided. One key allows changing the parameters of the protection functions. The other one is used to change the control modes. The sensor automatically detects which key has been inserted. The two keys are labeled “Protect” and “Control”, to distinguish them. When required, a general key to access both modes can be provided. It is also possible to program an 8 characters custom code in the keys to increase the security levels or for any other specific reason. This can be done very easily with a program available on request. Object Control. These push buttons allow operating the primary objects. Menu Navigation. These push buttons allow navigating trough the REF542plus menu. 8 x 4 pages user programmable leds. 8 freely programmable, three-color leds are available for indications. There are 4 pages of these leds. The assignment of the led to a specific condition is done with the Operating Tool.

PC interface. This is the optical serial interface port to connect the REF542plus with a personal computer. By using the appropriate cable and the Operating Tool, the following actions are possible: • Download a configuration into the unit, • Upload the current configuration from the unit, • Upload the fault recorder, • Upload other information (measurements, binary inputs status, binary output status). Measurements Bars. 3 freely programmable bars have been provided for a quick inspection of the switchgear load situation. The three bars are marked M1, M2, and M3. Each bar is composed of twelve leds: ten green and two red. The ten green leds are normally dedicated to display between 0% and 100% of the nominal value of the configured measurement, each led corresponding then to 10% of the nominal value. The two red leds indicates an overload condition of 20%. The measurement displayed by the bar is set with the Operating Tool. M1..M3 reference text can be configured and displayed on the display graphical side. Text. This is the textual part of the LCD. It shows the menu, the measurement values, the events and any information accessible through the menu structure. SLD view. This is the graphical part of the LCD. This part shows the single line diagram of the switchgear. The status of the primary objects is dynamically updated after every operation: if for example the circuit breaker has been opened, its representation will reflect it. CB Fast Opening. When pressed simultaneously with the normal open button, this button allows opening the circuit breaker, independently from the selected control mode. This feature must be enabled in the unit with the Operating Tool. Moreover, it is also possible to have several, completely user defined command buttons on the HMI. These virtual push buttons are available from the dedicated HMI menu. During REF542plus configuration, the user defines what command buttons are required. Typical examples might be: start of a transfer switch or of any other automation sequence, fault recorder activation, start of a load shedding sequence, etc. Thanks to the user defined command buttons, REF542plus automation capabilities can cope with any requirements.

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2 CONFIGURATION

Configuration

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2 CONFIGURATION

The REF542plus unit is configured for the specific application using the Operating Tool running on a personal computer. With the graphical editor, the needed functions blocks are combined together. The available protection functions are represented with specific function blocks, which can be combined with logic functions to define the required protection and automation scheme. This flexibility is very advantageous for defining control functions and automation sequences, which can, for example, include the interlocking of the switching devices, blocking the release of specific protection functions, as well as starting switching sequences. The REF542plus unit provides a wide range of logical functions so that each specific requirement can be met.

REF542plus graphical configuration.

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The functions includes any kind of logical gates such as AND, OR, timers, counters, pulse generators, flip-flops etc. All functions in the switchgear are specified in collaboration with ABB. The REF542plus configuration is a file, which is then downloaded into the unit via the optical serial port on the HMI. The Operating Tool allows also these additional functions, once connected to the HMI via the serial cable: • Protection functions setting • Measurement values read-out • On line binary inputs and outputs status readout • Fault recorder data acquisition. The Operating Tool allows on line, real time monitoring of the internal control signals and logic states, a powerful tool for applications debugging.

3 FUNCTIONS

Measurements

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Monitoring and self-diagnosis

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Protection

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Control

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Events and fault recording

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Time synchronization

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Interface to the primary process

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CAN Open

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Analog Output 4/0 … 20mA

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Analog Input 4 … 20mA

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Interfacing a Station Automation System

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Embedded Web Server

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FUNCTIONS

REF542plus Multifunction Protection and Switchbay Control Unit integrates all the secondary functions into a single unit. This multifunction unit also features a self-monitoring function. This versatility makes it possible to use the REF542plus on any switchgear independently from the specific required application.

The available measurements depend upon the analog input configuration. With the maximum configuration, the following are obtained. Directly acquired values • Phase currents; • Phase-to-ground or phase-to-phase voltages • Earth current (it can also be calculated); • Residual voltage (it can also be calculated); • Frequency.

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Measurements

(1) REF542plus can use both phase-to-phase and phase-to-ground voltage transformers. (2) When phase-to-ground voltage transformers are used. 12

REF542plus can have a maximum of 8 analogue input channels for measuring current and voltage signals. These channels are organized into three groups: three channels in group 1 and in group 2, two channels in group 3. Group 1 and group 2 have to be homogeneous, which means they can measure 3 currents or 3 voltages. For example, measurement of 1 current and 2 voltages is not allowed. Group 3 can get any type of signals: 2 currents, 2 voltages, 1 current and 1 voltage. REF542plus analogue inputs are very flexible, as this flexibility is needed to support all the protection functions. Group 1 and group 2 can be used for homogeneous current or voltage measurements either from instrument transformers or noninductive sensors. Group 3 can be used in a heterogeneous way, either with instrument transformers or with sensors. One of the most common configurations uses three current and three voltage inputs and one earth fault current input. All these values are shown on the HMI display. The following measurements, registered over an extended period of time, are permanently saved in non-volatile memory: • Operating hours; • Active and real energy; • Max and average current for each phase; • Max voltage (available only from the communication module); • Average voltage (available only from the communication module); • Sum of interrupted currents; • Number of switching cycles; • Fault recorder data; • HMI Key status. After a power supply loss, this data is still available.

From the above, the following values can be calculated. Computed values • Phase voltages(2), • Average/maximum current value, three-phase (determined over several minutes); • Apparent, active and reactive power; • Power factor; • Active and reactive energy; • THD (Total Harmonic Distortion).

Monitoring and self-diagnosis The REF542plus offers several features for monitoring the primary part as well for selfdiagnosis. The following computed quantities are available for primary part monitoring: • Maximum and mean currents in the observation period (0 ... 30 min); • Sum of interrupted currents; • Working hours; • Number of switching cycles (open-close circuit breaker); • Spring charging time supervision (when applicable); • Opening coil supervision. The REF542plus is equipped with self-diagnosis routines that constantly check the hardware and software modules status; every REF542plus binary input and output module is equipped with a watchdog contact that triggers in case of fault or power loss. This contact can be used to detect unit failure and to initiate the appropriate actions. Analogue input channels can be optionally supervised. A broken wire in the connection with an instrument transformer or a sensor can be detected and an alarm can be activated.

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Protection The REF542plus offers a wide range of protection functions to cover all medium voltage applications. These protections can be combined together to implement the required scheme. When directional protections are used, some binary inputs and outputs can be dedicated to the logic selectivity. The following protections and related functions are available. Current Protection • Inrush blocking (68) • Overcurrent Instantaneous (50) • Overcurrent definite time, 2 thresholds (51) • Overcurrent directional, 2 thresholds (67) • Overcurrent IDMT (51 IDMT) • Earth fault, 2 thresholds (51N) • Earth fault IDMT (51 IDMT) • Earth fault directional, 2 thresholds (67N) • Earth fault directional sensitive (67S) • Earth fault directional sector (67NS), 10 thresholds.

Voltage protection • Over voltage Instantaneous (59) • Over voltage definite time, 2 thresholds (59) • Under voltage Instantaneous (27) • Under voltage definite time, 2 thresholds (27) • Residual over voltage, 2 thresholds (59N) Line Protection • Distance (21) Differential Protection • Differential protection for motors and transformer (87) • Restricted earth fault for transformer (87N) Thermal protection • For cables, motors and transformers (49) Motor specific protection • Number of starts counting (66) • Locked rotor (51LR) • Motor start (51MS) • Low load (37) • Unbalanced load (46)

Other protections and related functions • Frequency protection (81), 6 thresholds per net • Synchrocheck (25) • Fault recorder • Autoreclosure (79) • Lock out (86) • Reverse power (32). At most 24 protection functions can be instantiated inside the REF542plus unit. The maximum number is anyway dependent upon the available processing power.

Control The control and automation capabilities inside the REF542plus are extremely powerful. Traditional wired logic with electromechanical relays is replaced by software control schemes inside the unit. Simple interlocking against switching errors as well complex load shedding schemes can be easily implemented with the control possibilities offered by the REF542plus. It is also possible to implement interlocking between switchbays connected to the same bus bar system. This requires the availability of status information of the switching devices to and from other switchgear. The status information must be provided by: • Conventional, hard-wired ring bus system; • Using the ABB station automation system allowing horizontal communication among the REF542plus units connected on the interbay bus; • Using the CAN Open digital fieldbus. The REF542plus foresees different control modes, selectable with the control key. In local mode, the HMI control buttons are used to operate on the primary objects. Remote operations are inhibited. In remote control mode, only switching actions from a remote control device like a station automation system are permitted. Local control from the HMI is inhibited. All the possibilities to operate on the primary objects can be inhibited setting the unit to the no control mode.

Power Quality Mitigation • Power factor controller (55) • Switching resonance protection • THD Protection 13

FUNCTIONS

The picture below shows an example of a circuit breaker control scheme.

Circuit breaker control scheme.

Events and fault recording The last thirty recorded events can be shown locally on the HMI display. Most of events are related to protection activities. The event type and additional information such as involved protection function, time and date, RMS value of the interrupted current are registered. The REF542plus unit can transmit the events to the station automation, when connected to it. Events are stored in non-volatile memory, so they are maintained also in case of power loss.

Event list on the HMI LCD. 14

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Fault recorder The REF542plus unit is equipped with a powerful and flexible fault recorder function. This function can be used to record at most eight analog input channels and thirty-two binary signals. The analog input signals are recorded with a sampling rate of 1.2 kHz for a time interval of at least 1 second and for a maximum of 5 seconds. The recording time is a combination of pre- and post fault time. The total recording capability is of 5 seconds: there can then be configured 5 records of 1 seconds or a single record of 5 seconds. The recording can be started by a protection event, by a binary signal change or by any user defined condition.

Fault records can be transferred locally to a personal computer from the HMI optical port with the Operating Tool on from the communication interface. When extracted with the Operating Tool or from the embedded WEB Interface, the fault records are automatically converted into the standard COMTRADE format. When retrieved from the communication interface, they can be converted with a utility program. Fault records are stored in non-volatile memory, so they remain available also after a power loss.

Record of a cross-country fault.

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FUNCTIONS

Time synchronization REF542plus is equipped with an internal real time clock, which is used to time stamp events. The internal clock is buffered by a special super capacitor. In case of power loss, the stored electrical energy in the capacitor ensures the internal clock operation for at least twenty-four hours. The date and time of the clock can be set via the HMI Control Unit. REF542plus internal clock can be kept synchronized to an external clock in different ways. When connected to a station automation system, REF542plus can be kept synchronized via interbay bus using the facilities of the used protocol, if available. Accuracy depends upon the protocol features and may vary from 3 ms (LON LAG 1.4) to tens of milliseconds (SPABUS). When better accuracy is required, REF542plus can be synchronized using the dedicated optical input port and a master clock, typically a GPS. The accepted time formats are IRIG format B000, B002 and B003. The picture shows the time distribution architecture for the synchronization. When synchronized through IRIG B, REF542plus unit guarantees an accuracy better of 1 ms and a resolution of +/- 500us. Very precise fault analysis is then possible.

Interface to the primary process REF542plus unit offers a very flexible interface to the primary process, to acquire analog measurements, to get binary signals and to send switching commands. Analog inputs The REF542plus unit has available at most eight analog input channels for voltage and current measurements. The unit can connect both conventional instrument transformers and noninductive sensors. Thanks to their linear characteristic, non-inductive sensors provide greater accuracy and reliability in signal measurement. Compared to conventional instrument transformers, sensors have some unique qualities directly affecting both the manufacture and the use of the switchgear. Some of these features are: • Linearity; 16

GPS satellite Satellite antenna Substation Master clock

Switchboard starcoupler

Substation Master clock and distributor

Synchronization of the internal clock by a GPS master clock and IRIG B port.

• • • • •

Wide rated range; No accuracy versus burden calculation; Standardized components; No saturation, no ferroresonance; Combined current and voltage sensor together in the same physical unit. The current sensor is based on the principle of the Rogowski coil, which consists of a single air-cored coil. Due to the lack of an iron core, the saturation effects of conventional current transformers do not exist anymore. Current sensors are thus well suited to be used with the distance and the differential protection functions. The current sensor output is a voltage signal proportional to the derivative of the primary current being measured. The numerical integration of the signal is performed by the DSP inside the REF542plus unit. Four current sensors only with nominal currents 80–160A, 160-480A, 480-1250A, 1600-3200A cover all the applications.

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The voltage sensor is based on the resistive divider principle, the measuring signal is directly proportional to the measured value and it cannot saturate. The signal is thus linear throughout the whole measuring range. The output signal is a voltage that is directly proportional to the primary voltage. The figure shows an example of a combined sensors. The current and voltage sensors are encapsulated into a single resin unit, and that is the reason why they are often referred as combined or combi sensors. Coupling electrode is incorporated in the sensor, for voltage detecting systems (VDS) or for voltage presence indicating systems (VPIS). Binary inputs and outputs The REF542plus unit acquires the primary objects status with auxiliary contacts, which are read by binary inputs, and sends commands using binary outputs. Several signals coming from other components are also monitored. Among the others, the following operations are implemented using binary inputs and outputs: • Primary objects control and interlocking in the switchgear; • Primary objects status acquisition (e.g. circuit breaker in opened/closed position); • Circuit breaker spring supervision (when applicable). Binary inputs are isolated by opto-couplers. Binary outputs can be implemented either with mechanical relays or with static (semiconductor) devices. In a switchgear with directly driven motors, static power outputs are usually required.

Combined sensor in Block type (DIN) execution.

In addition, the digital bus moves “the intelligence” closer to the process, allowing the construction of switchgear systems with increased configuration and maintenance flexibility. The CAN Open interface allows connecting any off-the-shelf product compliant with the CAN Open standard, thus making the automation capabilities of the REF542plus almost unlimited. The picture below describes an architecture where two REF542plus units and some IO modules are connected with the CAN Open.

I/O modules

FIELDBUS

REF542plus

CAN Open The REF542plus is equipped on the main module with a CAN Open standard interface. The CAN Open interface has two main purposes: • Replacing the switchgear internal hard-wired connections by means of a high-speed digital bus; • CAN Open standard devices connectivity (intelligent IO modules, sensors, ...). Replacing the switchgear internal hard-wired connections by means of a high-speed digital bus allows building new highly standardized switchgear with a more efficient life cycle. Fast interlocking data among several REF542plus units can be exchanged on the CAN Open bus.

REF542plus configuration tool Intra-panel wiring

Circuitbreaker

Network management tool

Panel A

Panel B REF542plus CAN Open connectivity. 17

FUNCTIONS

Analog Output 4/0 … 20 mA module

Interfacing a Station Automation System

An optional analog output module with four configurable channels can be placed in the Base Unit. The output signal of this module can be set in the range from 0 to 20 mA or 4 to 20 mA. Each of the four channels can be independently configured. The following quantities are selectable to be transmitted: • Voltage measurements, both directly acquired and calculated; • Current measurements, both directly acquired and calculated; • Apparent, active and reactive power; • Cos phi; • Frequency.

An optional communication module can be provided for interfacing a station automation system. The four different protocols available for the REF542plus make possible to interface any kind of station automation system, both from ABB or from third parties.

Analog Input 4 … 20 mA module

(*) Only passive sensors can be connected to the analog input 4 ... 20 mA module. The module itself supplies the sensor.

An optional analog input module with six channels can be placed in the Base Unit (wide housing only). These input channels work accordingly to the 4 ... 20 mA current loop. Different type of sensors (temperature, gas density, etc.) can be connected to these channels. The sensor signal is acquired on the 4..20mA channel. Inside the REF542plus the sensor signal is treated in a binary way. When the sensor signal is above the set threshold, its corresponding logic signal becomes active. The analog input module is placed in the same slot of the analog output module; analog input module and analog output module are then mutually exclusive (*).

MicroScada station control

The following typical functions are then possible: • Primary objects status monitoring; • Primary objects control; • Protections parameterization; • Measurements, alarms end events acquisition; • Fault recorder data acquisition. These are the available protocols: • SPA-bus; • LON-bus according to ABB Lon Application Guide (LAG) 1.4 definitions; • Modbus RTU; • IEC 60870-5-103 with the extensions for control functions according to VDEW (Vereinigung Deutscher Elektrizitätswerke = association of German utilities). The first two protocols, SPA-bus and LON according to LAG 1.4, are ABB specific, while Modbus RTU and IEC 60870-5-103 guarantee open connectivity to any third party system. The picture below shows a few REF542plus units connected with LON to an ABB system. The LON LAG 1.4 protocol has specific features for high accuracy time synchronization; in this case the REF542plus units are synchronized from the interbay bus. Moreover, the presence of the Ethernet port on the REF542plus extends the potential future connectivity of the REF542plus unit. Both Modbus RTU and Spabus protocols can run on a module equipped with two serial channels. The simultaneous use of the two serial channels as physical redundancy is not possible. The connection to two different SCADA system is possible (for the Spabus, provided that one of the two SCADA is for monitoring purposes only).

GPS Clock

1,25MB/s LON LAG 1.4 (optical interface) RER111 Starcoupler

REF542plus

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REF542plus

REF542plus

RE542 plus units connected to an ABB station automation system. Time synchronization is done over the interbay bus.

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Embedded WEB Server REF542plus can be equipped with an embedded WEB server for monitoring purposes (WEB REF). The Ethernet port on the main module provides connectivity to the WEB. By using a standard PC with a commercial WEB browser, the user can gain access to the substation units using the WEB facilities. Monitoring the substation units is then possible from everywhere; the implemented security mechanism prevents unwanted accesses and guarantees the required safety. As soon as the browser is connected to the REF542plus unit, the switchgear overview is displayed. From here, the user can scroll through the single line diagram. Clicking on the address button, the specific REF542plus unit single line diagram is loaded, with also all the information that would be normally available standing in front of the HMI. REF542plus data are available in read mode only (monitoring access). WEB REF makes also available the possibility to send SMS messages via the GSM network upon specific, user defined condition (trips, alarms, etc.). A suitable GSM modem must be connected to the mainboard module.

Motor Control

Network Communication

Local and remote / Operational

Monitor

Alarm

WEBREF

Interlocking error

2002/12/13 14:42:30

Control Protection

Service Configuration

Last update

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English

Deutsch

Help

Control

Single Line Diagram M1 0%

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REF542plus main page as seen from the Internet browser.

WEBREF

WEB Switcboard Feeder 1

Motor

M1: IL1 M1: U1E

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Switchgear equipped with REF542plus: single line diagram as seen from the Internet browser. 19

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4 APPLICATION EXAMPLES

Automatic transfer switchover

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High speed transfer system (HSTS)

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Motor management

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Power transformer management

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Distribution networks management

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Overhead and cable lines

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Power quality

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APPLICATION EXAMPLES

This section illustrates a few typical REF542plus applications; where its flexibility is of utmost advantage both in terms of safety of operations and cost effectiveness. In all the following applications, the REF542plus is the only unit installed in the switchgear. No additional relays or devices are needed. It is worth noting that in all the different applications, the REF542plus hardware is always the same, customized to the specific needs by means of software configuration only. The software customization guarantees several important benefits to the user: • Maximum flexibility also after switchgear commissioning, changes and extensions are done via software. No new wirings are needed. • One kind only of spare parts instead of several different relay types for incoming feeders, motor feeders etc. Spare parts costs are kept at the real minimum. • One human machine interface only to learn.

Automatic transfer switchover The REF542plus unit can be used in medium voltage switchgear for managing the automatic and manual switching between two different incoming lines.

Automatic transfer with REF542plus.

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Automatic switching is required in installations where the power supply must always be guaranteed to meet process continuity requirements. REF542plus carries out the automatic transfer switchover in about 500 milliseconds (circuitbreaker operating time included); the exact time value depends upon the software complexity of the required commutation logic. Switchgear equipped with suitably programmed REF542plus units constitute a complete, efficient system able of controlling the switching between one power supply system and another alternative one, or reconfiguring the network by switching from dual radial distribution to a single system in a fully automatic way. User personnel can also carry out the same switching manually from a station automation system or standing in front of the switchgear. Manual switching involves performing the parallel passing: the power supply lines are closed simultaneously using the synchro-check function when the two voltage vectors are synchronous, and then subsequently returning to the disconnected state when the switching has been completed. These applications do not require any instrumentation in addition to the REF542plus.

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High speed transfer system (HSTS) The classic automatic transfer switch described in the former paragraph is not always enough. In really demanding applications with very sensitive loads, such as paper mills, power plants, any voltage drop is catastrophic. In these situations, the transfer has to be the fastest. The automated load transfer to an emergency feeder in less than two cycles enables to avoid expensive downtime, and enhances the protected bus bar supply quality, providing at the same time full short circuit protection. Using fast circuit breakers such as VM1 T vacuum magnetic actuated type, when the two feeders are synchronous and all the other conditions are met, the REF542plus based high speed transfer system guarantees a switch over time of 30ms. The system is composed of: • the SUE 3000 controller • the REF542plus units • the VM1 T circuit breakers. SUE 3000 HMI high speed transfer controller with three breakers configuration.

The picture shows the system single line diagram for a two breakers configuration.

REF542plus feeder terminals Feeder 1

Feeder 2

VS/FDI

Fast VM1

VS/FDI

Fast VM1

SUE3000

Busbar

High speed transfer system with two breakers configuration architecture.

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APPLICATION EXAMPLES

Feeder 1 is normally closed and feeds the bus bar. Feeder 2 is the stand by alternative feeder. The two REF542plus units on Feeder 1 and Feeder 2 take care of the usual control and protection functions. In addition, they have active the voltage supervision VS/FDI (Voltage Sensing Fast Detection Indicator) function block to immediately detect and signal any power loss/drop. The VS/FDI allows alerting the SUE 3000 controller in less than 3ms. When the REF542plus feeder terminal 1 detects a power loss, it communicates it to the SUE 3000 that gives simultaneously the opening command to Feeder 1 and the closing command to Feeder 2. The SUE 3000 continuously monitors the two feeder voltages to verify that the proper conditions for the high speed transfer are met. The SUE 3000 compares, on a permanent basis, the phase angle and the frequency difference between the voltage of the bus bar and of the stand-by feeder. Also the voltage amplitude of the stand by feeder is verified, to be above a certain threshold. This continuous monitoring ensures that the minimum short transfer time is achieved, the transient effects of which represent no danger to the connected loads.

REF542plus motor management diagram. 24

Motor management The REF542plus unit is suitable for controlling and protecting medium voltage motors of any size. The motor can be actuated using both circuit breakers and contactors with mechanical or electric hold operating mechanisms. When configured accordingly, the REF542plus is able to manage motor shutdown, acceleration and restarting. Following a failure or transient voltage drop in the power supply, the REF542plus is able to supervise the motor disconnection and if required to send the command for re-insertion, in complete autonomy. Here below there is a typical example of motor management sequence. The installed motor control configuration intervenes when the power supply voltage falls below the set value that causes opening. The REF542plus unit starts then timing the power supply failure duration. When the power supply is restored, the REF542plus unit decides what action to take: – if the power supply failure time is less than the set acceleration time, it will close the actuator immediately, thus accelerating the motor; – if the power loss time is greater than the acceleration time but less than the restarting time, it will start timing a different delay motors by motors to switch them back in again in a predefined order; – if both time periods have been exceeded, the REF542plus unit will reset the procedure, awaiting an external command.

4

The sequence for the circuit-breakers being switched, the voltage thresholds, time delays and restarting enabling functions are configured in the REF542plus unit.

Power transformer management The protection of power transformers is the result of a compromise between technical and economical considerations. Also usual practices of the electrical system designer have a relevant importance in the choice of the protection functions scheme to be used. REF542plus offers a wide set of protections suitable for small, medium and large power transformers, to meet all the requirements. For small and medium sized transformers, usually over current and thermal protections are judged sufficient. The REF542plus unit via its digital inputs manages also other binary signals like the Buccholz realy. Differential protection and restricted earth fault Important transformers, with power of a few Mega Watts, or of particular relevance for the power distribution network, are often protected also by the differential protection against phase-to-phase faults. The restricted earth fault protection can be used when the neutral of the downstream system is connected to ground at the power transformer.

Distribution networks management The REF542plus unit, when used in distribution networks, provides the highest degree of selectivity for tripping in the event of faults, quickly isolating the fault equipment and leaving undisturbed the supply for the unaffected loads. Both ring and radial networks are controlled and protected by REF542plus units with the same effectiveness. The REF542plus offers a wide choice of directional protections. Two directional overcurrent phase protection thresholds, two directional earth fault protection thresholds, one directional sensitive earth fault protection and ten threshold of the sector directional earth fault protection. Using these directional protection functions and suitable logic, the REF542plus identifies and locates faults (line bus bar or loads), isolates them by opening the smallest possible number of circuit breakers, to limit the supply switch off at the minimum. Logic selectivity between two REF524plus units can be achieved by means of wire connection; the maximum distance between the two neighboring units is about 1200 meters. Relay Opens

Ring network

Relay

Relay

B Circuit-breaker 67 Protection function C Forward D Backward

Radial network

25

APPLICATION EXAMPLES

Overhead and cable lines Medium voltage overhead lines for power distribution are considerably shorter than overhead high voltage lines for power transmission. Nevertheless, medium voltage lines are subjected to the same kind of faults: both transient like tree arms fallings and permanent like conductor breakdown. Fault detection and elimination is in some case problematic, especially in complex meshed networks. The REF542plus distance protection is very suitable to be used for medium voltage distribution lines protection in networks with meshed topology. The REF542plus distance protection can be indifferently used in pure cable networks, pure overhead line networks and mixed installations (cable-overhead line or overhead line-cable). The neutral can be insulated, directly grounded or grounded with impedance. The distance protection is used for short circuits selective interruption using the fault impedance as the main discriminating quantity. The impedance between the point where the protection device is installed and the point where the fault has occurred is measured on the outgoing line. If the impedance value is lower than the set value, a trip is issued and the line is interrupted.

Zones configuration and I-Z plane diagram.

26

The fault location is indirectly identified using the impedance per unit of length of the line. In this case, the line impedance Z (with a homogeneous line) is proportional to the fault distance. The distance protection comprises a starting logic, an impedance measuring logic and a direction identification logic. • Starting logic: it detects the fault condition. • Impedance measuring logic: it determines the distance of the zone in which the fault has occurred. • Direction identification logic: it verifies whether the fault is located in the same direction as the line being protected. The REF542plus distance protection offers 5 different zones, 2 of them for predefined use (overreach and directional back up). There is also a non-directional tripping zone, independent from the impedance, for back up. The extremely flexible auto reclosing function complements the REF542plus distance protection. For example, in case of mixed cable-overhead lines sections, it is possible to block the auto reclosing function for cable faults using the autoreclosing stop zone. The pictures show an example of zones configuration and I-Z plane diagram.

4

Power quality The REF542plus is equipped with functions both to monitor and to increase the power quality. Industrial loads are becoming more and more sensitive to power quality parameters like harmonic contents; while utilities billing policy penalize poor power factor. Integrated power factor controller with resonance protection The REF542plus unit offers a power factor controller able to switch up to four capacitor banks. This function allows integrating the reactive power compensation in the medium voltage switchgear, without the need of additional components. Rated power up to tens of Mvar can be switched on and off to follow the set target power factor for any load conditions. A problem that might occur when power factor correction capacitors are switched on is harmonic resonance. The power system becomes tuned to a specific frequency due the combination of the loads inductance and the added capacitance. The power system is then resonating at this frequency. Harmonic resonance results in severe voltage and current distortions, with increased losses and equipment overheating.

The resonance protection (ABB patented) in the REF542plus unit prevents these dangerous resonance conditions. Sensing the increase in the harmonic content, the resonance protection switches off the inserted bank, de-tuning the power system. Depending on the setting, the power factor controller can then undertake other remedial actions to follow the set target power factor. The following figure shows the voltage total harmonic distortion (THD) increase when switching on a capacitor bank. The THD remains above the set trip threshold level after the typical hundred of milliseconds of the transient. The resonance protection then clears the dangerous condition switching off the capacitor bank.

THD protection Harmonics have significant unwanted impact on power distribution systems and the loads they feed. Typical negative effects are overheating, current demand increases, over voltages. Negative sequence harmonics reduce forward torque in motors, while increasing the current. REF542plus THD (Total Harmonic Distortion) protection prevents these negative effects. The protection issues the trip when the harmonic content is higher than the set threshold. The content is analyzed up to 1500Hz, which results in the 25th harmonic for 60Hz system and the 30th for 50Hz one.

Resonance condition caused by switching on a capacitor bank. 27

28

5 CONSTRUCTION

Base Unit versions

30

External dimensions

30

Mounting and installation

31

29

CONSTRUCTION

Base Unit versions The REF542plus Base Unit housing is made from aluminum sheets. Its exterior is chromatized both to protect the housing against corrosion and to improve immunity against EMC disturbances. Two different housings are available: • Standard, • Wide. In both versions, at least the following modules have to be present: • the power supply, the mainboard, the analog input module, one binary input and output module. The standard housing can additionaly house: • another binary input and output module, • alternatively the communication module or the 4/0 ... 20 mA analog output module.

Backplane differs from 4/0 ... 20 mA analog output module and communication module. The backplane type has to be specified. The wide housing can additionaly house: • other 2 binary input and output modules, • the communication module, • alternatevly the 4/0 ... 20 mA analog output module or the 4 ... 20 mA analog input module. Note: the 4 ... 20 mA analog input module can be used with the wide housing only. Standard housing summary • One power supply; • One mainboard module; • One analog input module; • At most two binary input and output modules; • Optionally the communication module or the 4/0 ... 20 mA analog output one.

External dimensions

Standard housing version dimensions. 30

Wide housing version dimensions.

5

Wide housing summary • One power supply; • One mainboard module; • One analog input module; • At most three binary input and output modules; • Optionally the communication module; • Optionally the 4 ... 20 mA analog input module or the 4/0 ... 20 mA analog output module.

Mounting and installation The picture shows an example of wide housing Base Unit installation inside the low voltage compartment. Thanks to the slider shown on the left, the time required to dismount the Base Unit or to replace a module is extremely short. Four bolts keep the unit in place (*).

Base Unit installation

HMI The HMI dimensions are shown in the following picture.

HMI dimensions.

(*) Slider is not included in the scope of the supply. 31

32

6 TECHNICAL DATA

Analog inputs and measurements

34

Protection functions technical data

37

Configuration restriction

42

Binary inputs and outputs

43

Interfaces

44

Power supply

45

Environmental conditions

45

Protection degree

45

Type test

45

33

TECHNICAL DATA

Analog inputs Measurements The REF542plus unit uses the same analog inputs both for measurements and protections. The measurement classes are according to the following table. Quantity

Accuracy

Range

Phase current, earth current

0.5%

0.1-4In

Line voltage, phase voltage

0.5%

0.2-1.5Vn

Active, reactive, apparent power

1%

-

Active, reactive energy

2%

-

Cosϕ

1%

0…1

Frequency

0.02%

-

To achieve highest accuracy the instrument transformers or the sensors must have 0.5% accuracy or better in the same range.

Protection Class 3.

Current and voltage transformer input values Rated current In

0.2 A or 1 A or 5 A

Rated voltage Un

100 V ... 125 V

Rated frequency fn

50 Hz / 60 Hz

Thermal load capacity Current path

250 In (peak value), dynamic 100 In for 1s, 5 In continuous

Voltage path

2 Un /√3 continuous

Consumption Current path

< 0.1 VA with In

Voltage path

< 0.25 VA with Un

Current and voltage sensor input values

34

Voltage at rated current In

150 mV (rms)/50 Hz/60Hz

Voltage at rated voltage Un

2V (rms)

Rated frequency fn

50 Hz/60 Hz

6

Analog input modules Several different types of analog input modules are available, to cope with the different protection functions. The modules are equipped with the following combinations of input current and/or voltage transformers: • 3 or 6 current transformers for phase currents; • 3 or 6 voltage transformers for phase-to-ground or phase-to-phase voltages; • 1 or 2 current transformers for residual currents; • 1 or 2 voltage transformers for residual voltages. There are also versions for sensor inputs and mixed ones, to connect both conventional instrument transformers and sensors. At most, eight input channels are available. If programmed, input channels can be supervised. The following analog input types are available: (S means sensor input, CT means Current Transformer input, VT means Voltage Transformer input). Other combinations are available upon specific request.

Code

Description

1VCF 750170R0804

3 CT+3 VT+1 CT 0.2A+1 VT

1VCF 750170R0806

3 VT+3 VT+1 CT 0.2A+1 CT 0.2A

1VCF 750170R0807

3 CT+3 CT

1VCF 750170R0809

3 CT+3 CT+1 CT 0.2A+1 VT

1VCF 750170R0812

3 VT+3 VT+1 VT

1VCF 750170R0817

3 CT+3 VT+1 CT

1VCF 750170R0819

3 CT+3 VT+1 CT+1 VT

1VCF 750170R0821

3 CT+ +1 CT

1VCF 750170R0822

3 CT+ +1 CT 0.2A

1VCF 750170R0824

3 CT+3VT+1CT+1CT

1VCF 750170R0825

3 CT+3 VT+1 CT 0.2A+1 CT 0.2A

1VCF 750170R0826

3 CT+3 VT+1 VT +1 VT

1VCF 750170R0827

3 CT+3 CT+1 CT +1 CT

1VCF 750170R0828

3 CT+3 CT+1 CT +1 VT

1VCF 750138R0803

3 S+3 S+1 S+1 S

1VCF 750170R0843

3 S+3 S+1 CT 0.2A+1 VT

1VCF 750170R0846

3 S+3 VT+1 CT 0.2A+1 VT

1VCF 750170R0847

3 S+3 S+1 CT

1VCF 750170R0851

3 S+3 S+1 CT+1 VT

1VCF 750170R0852

3 S+3 S+1CT 0.2A

1VCF 750170R0853

3 S+3 S+1 VT+1 VT

1VCF 750170R0854

3 S+3 CT+1 CT 0.2A+1 VT

1VCF 750170R0855

3 S+3 CT+1 CT 0.2A+1 CT 0.2A

35

TECHNICAL DATA

Reaction time In this context the protection reaction time is defined as the time elapsed between the fault detection and the closing of the contact that gives supply to the circuit breaker tripping coil (or the equivalent tripping mechanism for magnetic drive or contactors). This time is the sum of different intervals: 1 Fault detection time; 2 User defined pre set delay (for definite time protection functions); 3 Trip information processing; 4 Relay output contact actuation. The REF542plus is a protection and control unit and the programmed automation logic is executed cyclically in a PLC–style mode. The cycle time, in the range of ten millisecond, is depending upon the logic complexity. The REF542plus has an internal fixed compensation both for the relay output contact actuation time and for the logic execution time. Nevertheless, the actual trip information processing time depends upon the complexity of the actual logic programmed inside the unit.

36

As a result, the protection reaction time, in the worst case, can be the user-defined pre set delay plus twice the cycle time. • Direct channel In really demanding applications, the protection has to react as fast as possible and the system behavior has to be absolutely deterministic. The REF542plus offers then to the protection system designer the direct channel option. Using this option, the programmed logic execution flow inside the unit is skipped and the trip command is instantly delivered to the switching object representing the circuit breaker. All the interlocking conditions are nevertheless respected and assured. Should the circuit breaker be blocked for any reason, e.g. insufficient SF6 pressure, the trip command is not actuated. The direct channel option grants then an absolutely deterministic behavior to the REF542plus protection functions.

6

Protection functions technical data The table below illustrates the protection functions technical data. ANSI Code

Protection Function and parameters

Current protection functions 68 Inrush stabilization (only in connection with 50 and 51) N = 2.0 … 8.0 M = 3.0 … 4.0 Time = 200 … 100.000 ms 68 Inrush Harmonic Min current threshold = 0.05 ... 40.00 In Harmonic ratio threshold = 5.00 ... 50.00% Fault current threshold = 0.05 ... 40.00 In 50 Overcurrent instantaneous I>>> = 0.10 ... 40.00 In t = 15 ... 30.000 ms 51 Overcurrent high I>> = 0.05 ... 40.00 In t = 20 ... 300.000 ms 51 Overcurrent low I > = 0.05 ... 40.00 In t = 20 ... 300.000 ms 51 IDMT Overcurrent IDMT (inverse definite minimum time) Normal-, Very-, Extremely- or Longtime- inverse time characteristic Ie = 0.05 ... 40.00 In K = 0.05 ... 1.5 67 Overcurrent directional high I>> = 0.05 ... 40.00 In t = 40 ... 30 000 ms Direction = backward, forward 67 Overcurrent directional low IE> = 0.05 ... 40.00 In t = 40 ... 30 000 ms Direction = backward, forward

Earth Fault (1) 51N Earth fault high IE>> = 0.05 ... 40.00 In t = 40 ... 30 000 ms 51N Earth fault low IE> = 0.05 ... 40.00 In t = 40 ... 30 000 ms 51N IDMT Earth fault IDMT (inverse definite minimum time) Curve type= normal, very, extremely or long time inverse time characteristic Ie = 0.05 ... 40.00 In K = 0.05 ... 1.5

(1) The use of the current balance transformer (accuracy class 1) is recommended to apply the lowest setting (0,05 In). 37

TECHNICAL DATA

67N

67N

67S

67N Sector

Earth fault directional high IE>> = 0.05 ... 40.00 t = 40 ... 30.000 ms Vo = 0,02 ... 0,7 Un direction=forward, backward net type=isolated (sin ϕ), earthed (cosϕ) Earth fault directional low IE> = 0.05 ... 40.00 In t = 40 ... 300.000 ms Vo = 0,02 ... 0,7 Vn direction=forward, backward net type=isolated (sin ϕ), earthed (cosϕ) Earth fault directional sensitive I0 = 0.05 ... 2.00 In t = 100 ... 10.00 ms Angle α = 0 ... 20° Angle δ = -180 ... 180° Vo = 0.05 ...0.70 Un Earth Fault directional Sector (10 thresholds available) Direction = Enable (directional behavior)…Disable (non directional behavior) Start Criteria = neutral current magnitude/ neutral current basic angle Io = 0,002…8,0 In Vo = 0,004…0,7 Un T = 30…60,000 ms Sector Basic Angle = -180° …180° Sector Width = 0.0 …360.0° Io drop off delay = 0…1.000 ms Vo drop off delay = 0…1.000 ms

Voltage protection functions 59 Overvoltage instantaneous U>>> = 0.10 ... 3.00 Un t = 15 ... 300.000 ms 59 Overvoltage high U>> = 0.10 ... 3.00 Un t = 40 ... 30.000 ms 59 Overvoltage low U> = 0.10 ... 3.00 Un t = 40 ... 30.000 ms 27 Undervoltage instantaneous U = 0.05 ... 3.00 Un t = 20 ... 300.000 ms

Motor protection functions 49 Thermal overload protection with total memory Nominal Temperature = 50 ... 400 °C (nominal temperature at I nom) Nominal current (IMn) = 0.1 ... 5.0 In (primary value of the nominal motor current) Initial Temperature = 10 ... 400 °C Time Constant at I < 0.1 IMn = 10 ... 100.000 s Time Constant at 0.1 IMn < I < 2 IMn = 10 ... 20.000 s Time Constant at I > 2 IMn = 10 ... 20.000 s Trip Temperature = 50 ... 400 °C Warning Temperature = 50 ... 400 °C Environmental Temperature = 10 ... 50 °C Reset Temperature = 10 … 400 °C 51MS Motor start (adiabatic characteristic) IMn = 0.2 ... 2 IMn (motor current) (2) Is = 1.00 ... 20.00 IMn (start value) t = 40 ... 30.000 ms I> = 0.2 ... 0.8 Is (motor start) 51LR Locked rotor (definite time characteristic) IMn = 0.2 ... 2.0 In (motor current) Is = 1.00 ... 20.00 IMn (start value) t = 40 ... 30.000 ms 66 Number of starts n (warm) = 1 ...10 (number of warm starts) n (cold) = 1 ...10 (number of cold starts) t = 1.00 .. 7200.00 s T (warm) = 20 ... 200 °C (warm start temp. thereshold) 46 Unbalance load Is = 0.05 ... 0.3 In (start value of the negative phase sequence) K = 2.0 ... 30.0 t Reset = 0 ... 2000 s Timer decreasing rate = 0 … 100% 37 Low load Pn = 50 ... 1000 000 kW (primary values) Minimal load P = 5 ... 100% Pn Minimal current I = 2 ... 20 % In Op. time = 1 ... 1000 s

(2) The motor temperature assumed by the number of starts protection is the one computed by the thermal overload protection (49). If the thermal overload protection is not used, the number of starts protection always assumes a cold start. 39

TECHNICAL DATA

Differential protection functions 87 Differential Transformer group = 0 ... 11 Transformer earthing = primary and or secondary side Nom. current In on the primary side of the transformer = 10.0 ... 100.000 A (prim value) Nom. current In on the secondary side of the transformer = 10.0 ... 100.000 A (prim value) Threshold current = 0.10 ... 0.50 In Unbiased region limit = 0.50 … 5.00 In Slightly biased region threshold = 0.20 ... 2.00 In Slightly biased region limit = 1.00 ... 10.0 In Slope = 0.40 ... 1.00 Trip by Id> = 5.00 ... 40.0 In Blocking by 2nd harmonic = 0.10 … 0.30 In Blocking by 5th harmonic = 0.10 … 0.30 In 87 N Restricted earth Fault (Restricted differential) Reference nominal current = 1.00 ... 100000.00 A Unbiased region threshold = 0.05 ... 0.50 In Unbiased region limit = 0.01 ... 1.00 In Slightly biased region slope = 0.01 ... 2.00 Slightly biased region limit = 0.01 ... 2.00 In Heavily biased region slope = 0.10 ... 1.00 Relay Operate Angle = 60° ... 180° Time = 0.04 ... 100.00 s Frequency protection function 81

Frequency protection Start value = 40 ... 75 Hz step 0.01 Frequency gradient = 0.01 1 Hz/s step 0.01 Time = 0.1 ... 30.0 s Undervoltage threshold = 0.1 ... 1 Un Trip logic = freq. only / freq. and gradient / freq. or gradient

Frequency supervision Frequency supervision Start value = 0.04 ... 5 Hz Time = 1 ... 300 s Distance protection function 21

Distance protection Net type = high/low ohmic earth start IE> used or unused switching onto faults = normal, overreach zone, trip after start Signal comparison overreach scheme time set = 30 …. 300.000 ms U / I- Start characteristic: I>, IE> and IF> = 0.05 ... 4.00 In UF< = 0.05 ... 0.9 Un Phase selection = cyclic/acyclic

40

6

Earth factor: k = 0.00 ... 10.00, ϕ (k) = -60 ... 60° 3 Impedance, 1 overreach stage and 1 autoreclose control stage: R = 0.05 ... 120 Ω (secondary values) X = 0.05 ... 120 Ω (secondary values) t = 20 ... 10.000 ms 1 directional stage Direction 0 ... 90 or -45 ... 135° t = 20 ... 10.000 ms 1 non directional stage t = 20 ... 10.000 ms Power Quality functions Power factor controller Switching sequence: linear, circular Switching histeresis: neutral zone 105 ... 200 % of Qco Pick up value: 0 ... 100 % of Qco Reactive power of smallest bank Qco: 1.000 ... 20.000 kVar Configuration banks: 1:1:1:1, 1:1:2:2, 1:2:2:2, 1:2:4:4, 1:2:4:8 Number of banks: 1 ... 4 Max switching cycles: 1 ... 10.000 Set point cos phi: 0.7 ... 1.000 Limiting value cos phi: 0.0 ... 1.00 Method of operation: direct integrating dicharge blocking time: 1 ... 7200 s dead time: 1 ... 120 s power on delay: 1 ... 7200 s duration of integration: 1 ... 7200 s High harmonic protection Voltage THD Startvalue = 5 ... 50% Voltage THD Time Delay = 0.01 ... 360.00 s Time = 0.05 ... 360.00 s Rms Voltage Startvalue = 0.10 ... 1.00 Un Switching resonance protection Voltage THD Start value = 5 ... 50% Delta Voltage THD Start Value = 1 ... 50 % Voltage THD Time Delay = 0.01 ... 60 s Time = 0.05 ... 60 s PFC OP Time = 0.01 ... 120 s Rms Voltage Start value = 0.1 ... 1.0 Un

41

TECHNICAL DATA

Other functions Fault recorder Recording time = 1000 ... 5000 ms Pre fault time: = 100 ... 2000 ms Post fault time = 100 ... 4900 ms Max. 5 records 79

Autorecloser Number of shots = 5 Reclaìm Time = 10 ... 1000 s Specìfic time first shot = 0.04 ... 30 s Dead time first shot = 0.10 ...100s Specific tìme second shot = 0.04 ... 30 s Dead time second shot = 0.10 ... 100 s Specific time third shot = 0.04 ... 30 s Dead time third shot = 0.10 ... 100 s Specìfic time fourth shot = 0.04 ... 30 s Dead time fourth shot = 0.10 ... 100 s Specific tìme fifth shot = 0,04 ... 30 s Dead time fifth shot = 0.10 ... 100 s

32

Directional power Direction = forward, backward Nominal real power Pn = 1 ... 1000 000 kW (primary values) Max. reverse load P> = 1 ... 50 % Pn Op. time = 1.0 ... 1000 s

Configuration restriction There are some limitations that must be respected during the REF542plus configuration. At most 24 protection functions can be configured inside the unit. A protection function can activate only one single direct channel. The number of direct channel is limited to 24. The configuration cycle time must be below 30ms, to guarantee the proper unit working. At most 1000 wires can be drawn, and the connections are limited to 512. Only one store object can be configured. (The store object allows storing binary data between a power fail and the next start up, see the programming manual for more details). At most 62 switching objects can be configured (a switching object is used to represent a primary object like a circuit breaker, a contactor etc.)

42

At most 15 energy counters can be configured. At most 10 analog threshold objects per analog input can be configured (analog threshold objects allow to undertake some actions depending upon the level of voltage and current, see the programming manual for more details).

LCD and HMI At most ten icons can be displayed on the LCD. At most eight switching devices icons can be displayed on the LCD. When binary I/O modules with mechanical relays are used, a maximum of seven switching devices can be controlled. At most, 40 lines can be drawn. At most 32 signaling leds organized in 4 pages can be configured. At most 48 Analog Warning Objects can be installed.

6

Binary inputs and outputs Binary input and output modules are available in two main versions: with electromechanical relays and with static outputs (power transistor types). For both of them, binary inputs are of the same type, insulated with optic couplers. Inside a REF542plus unit, only modules of the same type have to be present. It is not possible to have both static and electromechanical modules.

For both voltage ranges, the modules can be equipped with an optional static output (power transistor) on binary output 7, instead of the normal electromechanical contact. This static output is usually needed to feed external energy meters with pulses. To make wiring easier, there are also available board versions with the binary inputs minus (-) connected together on the module by an internal line.

BIO module with mechanical output relays (type 3) Binary input and output modules type BIO3 are available in several versions. • High voltage, with inputs able to withstand a voltage range from 85 up to 220VDC. The input threshold activation level is 50VDC. • Low voltage, with inputs able to withstand a voltage range from 24 up to 90VDC. The input threshold activation level is 14VDC.

The table below shows the main features. 14 input channels

Possible auxiliary voltage ranges: 20 to 90 V DC (threshold 14 V DC) 80 to 250 V DC (threshold 50 V DC) Hardware fixed filter time 1 ms. Additional filter time can be configured in software.

6 power outputs .

Maximum operating voltage

(channels BO 1 to 6)

Make current

250 V AC/DC 20 A

Load current

12 A

Breaking capacity

30 W with L/R 100MOhm at 500V DC.

Power consumption

< 30 W (Typical, 2 BIOs)

Inrush current

< 10 A peak value for 200 ms

Admissible ripple

Less than 10%

Mechanical robustness According to IEC 60255-21-1.

48 … 110 VDC (-15%, +10%)

Climatic conditions Cold test according to IEC 60068-2-1. Dry heat test according to IEC 60068-.2-2

HMI Rated voltage

110 … 220 VDC (-15%, +10%) Power consumption