ekorrp PROTECTION, METERING AND CONTROL UNITS

Transcription

1 General Instructions PROTECTION, METERING AND CONTROL UNITS LIB Transformer Substations Secondary Distribution Switchgear Primary Distribution Switchgear Protection and Automation Low Voltage Boards Distribution Transformers

2 Legal Deposit: 1457/2012 CAUTION! When MV equipment is operating, certain components are live, other parts may be in movement and some may reach high temperatures. Therefore, the use of this equipment poses electrical, mechanical and thermal risks. In order to ensure an acceptable level of protection for people and property, and in compliance with applicable environmental recommendations, Ormazabal designs and manufactures its products according to the principle of integrated safety, based on the following criteria: Elimination of hazards wherever possible. Where elimination of hazards is neither technically nor economically feasible, appropriate protection functions are incorporated in the equipment. Communication about remaining risks to facilitate the design of operating procedures which prevent such risks, training for the personnel in charge of the equipment, and the use of suitable personal protection equipment. Use of recyclable materials and establishment of procedures for the disposal of equipment and components so that once the end of their service lives is reached, they are duly processed in accordance, as far as possible, with the environmental restrictions established by the competent authorities. Consequently, the equipment to which the present manual refers complies with the requirements of section 11.2 of the forthcoming IEC standard It must therefore only be operated by appropriately qualified and supervised personnel, in accordance with the requirements of standard EN on the safety of electrical installations and standard EN on activities in or near electrical installations. Personnel must be fully familiar with the instructions and warnings contained in this manual and in other recommendations of a more general nature which are applicable to the situation according to current legislation. The above must be carefully observed, as the correct and safe operation of this equipment depends not only on its design but also on general circumstances which are in general beyond the control and responsibility of the manufacturer. More specifically: The equipment must be handled and transported appropriately from the factory to the place of installation. All intermediate storage should occur in conditions which do not alter or damage the characteristics of the equipment or its essential components. Service conditions must be compatible with the equipment rating. The equipment must be operated strictly in accordance with the instructions given in the manual, and the applicable operating and safety principles must be clearly understood. Maintenance should be performed properly, taking into account the actual service and environmental conditions in the place of installation. The manufacturer declines all liability for any significant indirect damages resulting from violation of the guarantee, under any jurisdiction, including loss of income, stoppages and costs resulting from repair or replacement of parts. Guarantee The manufacturer guarantees this product against any defect in materials and operation during the contractual period. In the event that defects are detected, the manufacturer may opt either to repair or replace the equipment. Improper handling of this equipment and its repair by the user shall constitute a violation of the guarantee. Registered Trademarks and Copyrights All registered trademarks cited in this document are the property of their respective owners. The intellectual property of this manual belongs to the manufacturer. In view of the constant evolution in standards and design, the characteristics of the elements contained in this manual are subject to change without prior notification. The validity of these characteristics, as well as the availability of components, are subject to confirmation by Ormazabal s Technical - Commercial Department.

3 GENERAL INSTRUCTIONS FOR CONTENTS 1. GENERAL DESCRIPTION GENERAL FUNCTIONAL CHARACTERISTICS PARTS OF THE UNIT COMMUNICATIONS AND PROGRAMMING SOFTWARE APPLICATIONS TRANSFORMER PROTECTION GENERAL PROTECTION LINE PROTECTION PROTECTION FUNCTIONS OVERCURRENT THERMOMETER (EXTERNAL TRIP) EARTH ULTRASENSITIVE DEVICE METERING FUNCTIONS CURRENT SENSORS CURRENT SENSORS TECHNICAL CHARACTERISTICS RATED VALUES MECHANICAL DESIGN INSULATION TESTS ELECTROMAGNETIC COMPATIBILITY CLIMATIC TESTS MECHANICAL TESTS POWER TESTS CE CONFORMITY PROTECTION, METERING AND CONTROL MODELS DESCRIPTION OF MODELS vs. FUNCTIONS RELAY CONFIGURATOR T UNITS G UNITS Page 3 of 84

4 GENERAL INSTRUCTIONS FOR IG-159-GB SETTING AND HANDLING MENUS KEYPAD AND ALPHANUMERIC DISPLAY DISPLAY PARAMETER SETTING TRIP RECOGNITION ERROR CODES MENU MAP (QUICK ACCESS) MODBUS PROTOCOL FOR RANGE UNITS READ / WRITE FUNCTIONS PASSWORD-PROTECTED REGISTER WRITING CRC GENERATION REGISTER MAP ANNEX A ANNEX B Page 4 of 84

5 GENERAL INSTRUCTIONS FOR 1. GENERAL DESCRIPTION The range of protection, metering and control units brings together an entire family of different equipment, which depending on the model, may incorporate protection functions as well as other functions such as local control, remote control, electrical parameter metering, automation, etc., related to the current and future automation, control and protection needs of Transformer and Switching Substations. Its use in Ormazabal s CGMCOSMOS, CGM-CGC and CGM.3 cubicle systems allows the configuration of customised products for meeting the diverse needs of the different installations. The protection, metering and control units have been designed to meet the national and international standard requirements and recommendations that are applied to each of the parts that make up the unit: EN 60255, EN 61000, EN , EN 60068, EN 60044, IEC 60255, IEC 61000, IEC , IEC 60068, IEC Page 5 of 84

6 GENERAL INSTRUCTIONS FOR IG-159-GB Designed to be integrated in a cubicle, the units also provide the following advantages over conventional devices: Reduction in handling of interconnections when installing the cubicle. The only connection required is limited to MV cables. Minimisation of the need to install control boxes on the cubicles. Avoidance of wiring and installation errors; minimisation of commissioning time. All the units are factory installed, adjusted and checked; each piece of equipment (relay + control + sensors) also undergoes a comprehensive check before being installed. The final unit tests are carried out once the unit is incorporated in the cubicle before delivery. They protect a broad power range with the same model (e.g.: G from 160 kva up to 15 MVA, in CGMCOSMOS system cubicles) GENERAL FUNCTIONAL CHARACTERISTICS All the relays of the units include a microprocessor for processing the signals from the metering sensors. They process current metering by eradicating the influence of transient phenomena and calculate the magnitudes needed for to carry out protection functions. In addition, the efficient electrical metering values, which provide the instantaneous value of these installation parameters, are determined. They are equipped with keypad for local display, setup and operation of the unit, as well as communication ports to handle these functions from a computer, whether locally or remotely. A user-friendly design has been employed, so that the use of the various menus is intuitive. The current is measured by means of several current sensors with a high transformation ratio, making it possible for the same equipment to detect a wide range of power levels. These transformers or current sensors maintain the accuracy class in all of their rated range. Page 6 of 84

7 GENERAL INSTRUCTIONS FOR The unit contains an events log where all of the latest trips made by the protection functions are registered. In addition, the total number of operations is saved as well as the unit's settings parameters. The local interface uses menus to provide the instantaneous values of the current metering for each phase and zero-sequence current, as well as the setting parameters, trip motives, etc. They can also be accessed via the communication ports. From a maintenance perspective, the units have a series of features that reduce the time and the possibility of errors in the test and service restoration tasks. The main features include some toroidal-core current transformers with larger diameters and test connections; accessible and disconnectable terminal blocks for tests using current injection; and built-in test contacts, even in the basic models PARTS OF THE UNIT The parts that form the protection, metering and control unit include the electronic relay, current sensors, power supply and test board, selfpowered toruses (only for selfpowered models) and the bistable trigger. Page 7 of 84

8 GENERAL INSTRUCTIONS FOR IG-159-GB Figure 1.2: Example of T unit installation in fused protection cubicles Page 8 of 84

9 GENERAL INSTRUCTIONS FOR Electronic Relay The electronic relay has keys and a display to set and view the protection, metering and control parameters. It includes a seal on the SET key to ensure that once the settings have been made they cannot be changed unless the seal is broken. The protection trips are registered on the display with the following parameters: reason for tripping, fault current value, tripping time and the time and date the event occurred. Errors in the unit, such as a switch failure, incorrect thermometer connection, low battery, etc., are also shown permanently. The 'On' LED is activated when the equipment receives power from an external source or the self-powered transformers. In this situation, the unit is operational to perform the protection functions. If the 'On' LED is not activated, only the unit's parameters can be viewed and/or adjusted (function exclusively assigned to the relay's internal battery). The current analog signals are conditioned internally by small and very accurate transformers that isolate the electronic circuits from the rest of the installation. The equipment has two communication ports, one on the front used for local configuration (RS232), and another one on the rear used for remote control (RS485). The standard communication protocol for all models is MODBUS. Others may be used depending on the application Current Sensors The current sensors are toroidal-core current transformers with a 300/1 A or 1000/1 A ratio, depending on the models. Their range of action is the same as the switchgear where they are installed. They are factory-installed in the cubicle bushings, which significantly simplifies the on-site assembly and connection. This way, once the MV cables are connected to the cubicle, the installation protection is operational. There are no sensor installation errors, due to earthing grids, polarities, etc. since they are previously installed and tested at the factory. Bushing Current sensors The inner diameter of the toroidal-core current transformers is 82 mm, which means they can be used in cables of up to 400 mm 2 without any problems for performing maintenance testing afterwards. If the equipment is selfpowered, the toroidal transformers are equipped with some anchorage points to place them in the same area as the metering transformers, thus forming a single, Page 9 of 84

10 GENERAL INSTRUCTIONS FOR IG-159-GB compact block. These transformers supply 1 W when the primary current is 5 A. This power is enough to allow the units to function correctly. All the current sensors have an integrated protection against the opening of secondary circuits, which prevents overvoltages Power Supply and Test Board The selfpowered equipment's power supply board prepares the selfpowered transformers' signal and converts it into a DC signal to safely power the equipment. The transformers permanently feed power from 5 to 630 primary amps to the board. It also has a 230 V ac input with 10 kv level of insulation. This input is for direct connection to the Transformer Substation's LVB. The power supply board of models with auxiliary power supply has an input for connecting both the AC (24 to 110 V ac ) and DC (24 to 125 V dc ) power supply. The board prepares the signal, converting it into a DC signal suitable for safely powering the equipment. Furthermore, both types of board have a built-in protection trip test circuit as well as connectors for carrying out current injection functional tests during maintenance and checking operations. The units also have a protection device for absorbing the excess energy produced by the transformers when there are short-circuits up to 20 ka Bistable trigger The bistable trigger is an electromechanical actuator that is integrated into the switch driving mechanism. This trigger acts upon the switch when there is a protection trip. It is characterised by the low actuation power it requires for tripping. This energy is received in the form of pulses lasting 50 ms and with an amplitude of 12 V. When there is a fault, these pulses are repeated every 400 ms to ensure that the switch opens. Page 10 of 84

11 GENERAL INSTRUCTIONS FOR 1.3. COMMUNICATIONS AND PROGRAMMING SOFTWARE All the units have two serial communication ports. The standard RS232 front port is used to set the local parameters with the ekorsoft program [1]. At the rear, there is an RS485 port which is used for remote control. The standard communication protocol implemented in all equipment is MODBUS-RTU (binary) transmission mode, although other specific protocols can be implemented depending on the application. This protocol has the advantage of greater information density than other modes, resulting in a higher transmission rate for the same communication speed. Each message must be transmitted as a continuous string and the silences are used to detect the end of the message. [1] For more information about the ekorsoft program, consult Ormazabal s IG-155 document. Page 11 of 84

12 GENERAL INSTRUCTIONS FOR IG-159-GB The ekorsoft setup program has three main operating modes: Display: indicates the unit status, including electrical measurements, current settings, date and time. User Settings: protection parameter change is enabled. Event Log: the parameters of the final and penultimate trip are shown as well as the total number of trips made by the protection unit. Minimum system requirements for installing and using the ekorsoft software: Processor: Pentium II RAM: 32 Mb Operating System: MS WINDOWS CD-ROM / DVD RS-232 serial port Page 12 of 84

13 GENERAL INSTRUCTIONS FOR 2. APPLICATIONS 2.1. TRANSFORMER PROTECTION The distribution transformers require various protection functions. Their selection depends primarily on the power and level of responsibility they have in the installation. As an example, the protection functions that must be implemented to protect distribution transformers with a power rating between 160 kva and 2 MVA are the following: 50 Instantaneous phase overcurrent. Protects against shortcircuits between phases in the primary circuit, or high value short-circuit currents between phases on the secondary side. This function is performed by the fuses when the protection cubicle does not include a circuit-breaker. 51 Phase overload. Protects against excessive overloads, which can deteriorate the transformer, or against short-circuits in several turns of the primary windings. 50N Instantaneous earth fault. Protects against phase to earth short-circuits or secondary winding short-circuits, from the primary interconnections and windings. 51N Earth Leakage. Protects against highly resistive faults from the primary to earth or to the secondary. 49T Thermometer. Protects against excessive transformer temperature. Protection units that include the above mentioned functions: System CGMCOSMOS Systems CGM-CGC / CGM.3 Unit Type of cubicle Power ranges to protect Power ranges to protect T Fuse-combination switch 50 kva kva 50 kva kva G Circuit-breaker 50 kva...15 MVA 50 kva...25 MVA See tables and Page 13 of 84

14 GENERAL INSTRUCTIONS FOR IG-159-GB GENERAL PROTECTION The client supply installations require general protection to ensure that an installation is disconnected from the rest of the network in the event of a fault. In this way, the Utility's supply line will remain energised and other clients will remain unaffected. It also protects the client's installation by disconnecting it from the power source in the event of a fault. In this type of protection, all the faults detected in the substation's main circuit breaker should be simultaneously detected in the transformer substations so that they can be cleared before the line trips (protection selectivity). 50 Instantaneous phase overcurrent. Protects against short-circuits between phases. 51 Phase overload. Protects against excessive overloads, which can deteriorate the installation. It is also used as a limiting device to control the supply's maximum power. 50N Instantaneous earth fault. Protects against phase-to-earth short-circuits. 51N Earth leakage. Protects against highly resistive faults between phase and earth. The following protection units provide the above-mentioned functions: System CGMCOSMOS Systems CGM-CGC / CGM.3 Unit Type of cubicle Power ranges to protect Power ranges to protect T Fuse-combination switch 50 kva kva 50 kva kva G Circuit-breaker 50 kva...15 MVA 50 kva...25 MVA See tables and Page 14 of 84

15 GENERAL INSTRUCTIONS FOR 2.3. LINE PROTECTION The purpose of the line protection is to isolate this part of the network in case of fault, without it affecting the rest of the lines. Generally, it covers any fault that originates between the Substation, or Switching Substation, and the consumption points. The types of fault that occur in these areas of the network primarily depend on the nature of the line, overhead line or cable and the neutral used. In networks with overhead lines, most faults are transitory. Hence, many line reclosings are effective. On the other hand, in case of phase-to-earth faults in overhead lines, when the ground resistance is very high, the zero-sequence fault currents have a very low value In these cases, an ultrasensitive neutral current detection is required. The underground cables have earth coupling capacities, which causes the single phase faults to include capacitive currents. This phenomenon makes detection difficult in isolated or resonant earthed neutral networks and thus requires the use of the directional function. Line protection is mainly accomplished by the following functions: 50 Instantaneous phase overcurrent. Protects against short-circuits between phases. 51 Phase overload. Protects against excessive overloads, which can deteriorate the installation. 50N Instantaneous earth fault. Protects against phase-to-earth short-circuits. 51N Earth leakage. Protects against highly resistive faults between phase and earth. 50Ns Ultrasensitive earth instantaneous overcurrent. Protects against phase to earth short-circuits of very low value. 51Ns Ultrasensitive earth leakage protection. Protects against highly resistive faults between phase and earth of very low value. Unit that includes the above mentioned functions: CGMCOSMOS / CGM-CGC / CGM.3 systems Unit Type of cubicle Maximum rated current G Circuit-breaker 630 A Page 15 of 84

16 GENERAL INSTRUCTIONS FOR IG-159-GB PROTECTION FUNCTIONS 3.1. OVERCURRENT The units have an overcurrent function for each one of the phases (3 x 50-51) and, depending on the model, they may have another one for earth (50N-51N). The implemented protection curves are the ones listed in standard IEC Overcurrent functions that can be performed depending on the model: Overload multicurve protection for phases (51). Protection of phase-to-earth multicurve faults (51N). Short-circuit protection (instantaneous) at a defined time between phases (50). Short-circuit protection (instantaneous) at a defined time between phase and earth (50N). Meaning of the curve parameters for phase settings: t(s) Theoretical tripping time for a fault which evolves with a constant current value. I Actual current flowing through the phase with the largest amplitude. I n Rated setting current. I> Withstand overload increment. K Curve factor. I>> Short-circuit current factor (instantaneous). T>> Short-circuit delay time (instantaneous). Pick-up current value of NI, VI, and EI curves = 1.1 x I n x I> Pick-up current value of DT curve = 1.0 x I n x I> Instantaneous pick-up current value = I n x I> x I>> In the case of earth settings, the parameters are similar to the phase settings. Each of them is described below. t o (s) Theoretical tripping time for an earth fault which evolves with a constant current value I 0. I o Actual current flowing to earth. I n Rated phase setting current. I o > Withstand earth leakage factor (phase). K o Curve factor. I o >> Short-circuit current factor (instantaneous). T o >> Short-circuit delay time (instantaneous). Pick-up current value of NI, VI, and EI curves = 1,1 x I n x I o > Pick-up current value of DT curve = 1,0 x I n x I o > Instantaneous pick-up current value = I n x I o > x I o >> Page 16 of 84

17 GENERAL INSTRUCTIONS FOR Page 17 of 84

18 GENERAL INSTRUCTIONS FOR IG-159-GB Page 18 of 84

19 84 GENERAL INSTRUCTIONS FOR 3.2. THERMOMETER (EXTERNAL TRIP) The equipment has an input for connecting volt-free contacts and tripping the switch. This input is protected against erroneous connections (e.g. 230 V ac ) showing an error code on the display when this anomaly occurs. The switch trips when the volt-free contact is closed for at least 200 ms. This prevents untimely tripping due to external disturbances. External tripping protection is disabled when all of the overcurrent protection functions are disabled (for firmware version 18 or later). In this situation, the relay will not trip the switch but a flashing arrow will appear at the top of the display screen to show that the external trip contact is closed (see section 8.4). The purpose of this function is to protect the transformers' maximum temperature. The trip input is associated to contact of the thermometer which measures the oil's temperature and when the maximum set value is reached, its associated contact closes and the switch trips. Unlike conventional coils, it has the advantage of not having low-voltage network connections with the consequent overvoltages generated in the control circuits. This trip input can also be associated to output contacts of remote control terminals, alarms and auxiliary relays responsible for opening the switch EARTH ULTRASENSITIVE DEVICE This protection corresponds to a particular type of overcurrent protections. It is primarily used in networks with isolated or resonant earthed neutral, where the phase-to-earth fault current value depends on the system cable capacity value and on the point in which the fault occurs. Generally, in Medium Voltage private installations with short cable stretches, simply determine a minimum zerosequence current threshold at which the protection must trip. 0-sequence toroidal transformer Page 19 of 84

20 GENERAL INSTRUCTIONS FOR IG-159-GB The current flowing to earth is detected using a toroidal-core current transformer which covers the three phases. In this way, the metering is independent from the phase current, thus avoiding errors in the phase metering transformers. In general, this type of protection must be used when the set earth current is less than 10% of the rated phase current (for example: for a rated phase current of 400 A with earth faults below 40 A). On the other hand, in the lines, whose cable stretches are usually long, it is necessary to identify the fault direction. Otherwise, trips can occur due to capacitive currents from other lines, when there is not any fault in the line. The available curves are: normally inverse (NI), very inverse (VI), extremely inverse (EI) and defined time (DT). The setting parameters are the same as in the earth faults of the overcurrent functions (section 3.1 Overcurrent), with the exception that factor I o > is replaced with the value directly in amps I g. This way, this parameter can be set to very low earth current values, regardless of the phase setting current. Pick-up current value of NI, VI, and EI curves = 1.1x I g Pick-up current value of DT curve = I g Instantaneous pick-up current value = I g x I o >> Page 20 of 84

21 84 GENERAL INSTRUCTIONS FOR 4. METERING FUNCTIONS 4.1. CURRENT The current values measured by the units correspond to the efficient values of each of the phases I 1, I 2 and I 3. Eight samples from a halfperiod are used and the mean of five consecutive values is calculated. This measurement is updated every second. It offers Class 1 meter accuracy, from 5 A up to 120% of the current sensor s maximum rated range. The zero-sequence current measurement I o is performed in the same way as the phase currents. Current meters: I 1, I 2, I 3 and I o 5. SENSORS 5.1. CURRENT SENSORS The electronic current transformers are designed for optimal adaptation to digital equipment technology, with a slight modification of the secondary interface. Therefore, the protection, metering and control equipment for these sensors operate with the same algorithms and with the same consistency as conventional devices. The low power outputs from the sensors can be adapted to standard values using external amplifiers. In this way, you can use conventional equipment or electronic relays. Page 21 of 84

22 GENERAL INSTRUCTIONS FOR IG-159-GB Main advantages derived from the use of sensor based systems: Small volume.the decreased power consumption of these transformers allows their volume to be drastically reduced. Improved accuracy. Signal acquisition is much more accurate due to high transformation ratios. Wide range. When there are power increases in the installation, the sensors do not have to be replaced with ones having a greater ratio. Greater safety. The open-air live parts disappear, increasing personnel safety. Greater reliability. The full insulation of the whole installation provides greater levels of protection against external agents. Easy maintenance. The sensors do not need to be disconnected when the cable or cubicle is being tested Functional Characteristics of Current Sensors The current sensors are toroidal-core current transformers with a high transformation ratio and low rated burden. These sensors are encapsulated in self-extinguishing polyurethane resin. Phase toroidal current transformers Range A Range A Ratio 300 / 1 A 1000 / 1 A Metering range 5 A to 100 A Extd. 130% 15 A to 630 A Extd. 130% Protection 5P20 5P20 Metering Class 1 Class 1 Burden 0,18 VA 0.2 VA Thermal current 20 ka 20 ka Dynamic current 50 ka 50 ka Saturation current 7,800 A 26,000 A Frequency Hz Hz Insulation 0,72 / 3 kv 0,72 / 3 kv Outer diameter 139 mm 139 mm Inner diameter 82 mm 82 mm Height 38 mm 38 mm Weight kg kg Polarity S1 blue, S2 brown S1 blue, S2 brown Encapsulation Self-extinguishing polyurethane Self-extinguishing polyurethane Thermal class B (130 ºC) B (130 ºC) Reference standard IEC IEC Page 22 of 84

23 84 GENERAL INSTRUCTIONS FOR Toroidal power transformers T / G Ratio 200/1 A with centre tap ( A) Power supply range 5 A to 630 A Thermal current 20 ka Dynamic current 50 ka Power 0.4 VA to 5 A Frequency Hz Insulation 0,72 / 3 kv Outer dimensions 139 mm Inner dimensions 82 mm Height 38 mm Weight kg Polarity S1 blue, S2 brown Encapsulation Self-extinguishing polyurethane Thermal class B (130ºC) Phase toroidal transformer 0-sequence toroidal transformer Page 23 of 84

24 GENERAL INSTRUCTIONS FOR IG-159-GB Vector Sum/Zero-SequenceWiring The wiring of the aforementioned transformers is performed in two different ways, depending on whether they have a zero-sequence toroidal current transformer installed or not. As a general rule, the zero-sequence toroidal transformer is used when the earth fault current is a below 10% of the phase current rating. R S T DETECTION OF EARTH CURRENT BY VECTOR SUM Page 24 of 84

25 84 GENERAL INSTRUCTIONS FOR Zero-sequence Toroidal Current Transformers Range A Range A Ratio 300 / 1 A 1000 / 1 A Metering range 0.5 A to 50 A Extd. 130% 0.5 A to 50 A Extd. 130% Protection 5P10 5P10 Metering Class 3 Class 3 Burden 0.2 VA 0.2 VA Thermal current 20 ka 20 ka Dynamic current 50 ka 50 ka Saturation current 780 A 780 A Frequency Hz Hz Insulation 0,72 / 3 kv 0,72 / 3 kv Outer dimensions 330 x 105 mm 330 x 105 mm Inner dimensions 272 x 50 mm 272 x 50 mm Height 41 mm 41 mm Weight 0.98 kg 0.98 kg Polarity S1 blue, S2 brown S1 blue, S2 brown Encapsulation Self-extinguishing polyurethane Self-extinguishing polyurethane Thermal class B (130 ºC) B (130 ºC) Reference standard IEC IEC Page 25 of 84

26 GENERAL INSTRUCTIONS FOR IG-159-GB 6. TECHNICAL CHARACTERISTICS 6.1. RATED VALUES Power supply AC 24 V ac V ac +/-30% DC 24 V dc V dc +/-30% Selfpowered >5 A, 230 V ac +/-30% Consumption < 1 VA Current inputs Primary phase 5 A A (depending on model) Earth 0.5 A A (depending on model) I thermal/dynamic 20 ka / 50 ka Impedance 0.1 Ω Accuracy Time delay 5% (minimum 20 ms) Metering / Protection Class 1 / 5P20 Frequency 50 Hz; 60 Hz +/-1% Output contacts Voltage 250 V ac Current 10 A (AC) Switching power 500 VA (resistive load) Temperature Operating - 40 ºC to + 70 ºC Storage - 40 ºC to + 70 ºC Communications Front port DB9 RS232 Rear port RS485 (5 kv) RJ45 Protocol MODBUS (RTU) 6.2. MECHANICAL DESIGN IP rating Terminals IP2X In cubicle IP3X IP4X (according to IEC ) IK06 (according to EN 50102) Dimensions (h x w x d): 146 x 47 x 165 mm Weight 0.3 kg Wiring Cable/Termination mm INSULATION TESTS IEC Insulation resistance 500 V DC : > 10 G Electric strength 2 kv ac ; 50 Hz; 1 min Voltage impulses: standard 5 kv; 1.2/50 s; 0.5 J differential 1 kv; 1.2/50 s; 0.5 J 6.4. ELECTROMAGNETIC COMPATIBILITY IEC Voltage dips 200 ms Ripple 12 % IEC Damped wave 1 MHz 2.5 kv; 1 kv IEC Electrostatic discharges 8 kv air (IEC , class IV) 6 kv contact IEC Radiated fields 10 V/m (IEC , class III) IEC Bursts - Fast transients ± 4 kv (IEC ) IEC Overvoltage pulses (IEC ) 4 kv; 2 kv Page 26 of 84

27 84 GENERAL INSTRUCTIONS FOR IEC Induced radio frequency 150 khz MHz signals (IEC ) IEC Magnetic fields 100 A/m; 50 Hz constant 1000 A/m; 50 Hz short- time (2 s) IEC Sinusoidal damped wave 2.5 kv; 1 kv IEC Electromagnetic emissions (EN ) 150 khz to 30 MHz (conducted) 30 MHz to 1 GHz (radiated) 6.5. CLIMATIC TESTS IEC Slow changes. Cold - 40 ºC; 16 hrs ºC; 16 hrs. IEC Slow changes. Heat + 60 ºC; 16 hrs ºC; 16 hrs. IEC Damp heat, continuous test + 40 ºC; 93%; 10 days IEC Damp heat cycles + 55 ºC; 6 cycles 6.6. MECHANICAL TESTS IEC Sinusoidal vibration. Response Hz; 1 g Sinusoidal vibration. Endurance Hz; 2 g IEC Impacts. Response 11 ms; 5 g Impact. Endurance 11 ms; 15 g Shock. Endurance 16 ms; 10 g IEC Seismic tests 1-38 MHz, 1g vertical, 0.5 g horizontal 6.7. POWER TESTS IEC No-load cable making and 24 kv/50 A/ cosφ = 0.1 breaking IEC Mainly active load making and 24 kv/630 A/ cosφ = 0,7 breaking IEC Earth faults 24 kv/200 A/50 A No-load transformer making and 13.2 kv /250 A/1250 kva breaking IEC Short-circuit making and breaking 20 ka / 1s 6.8. CE CONFORMITY This product complies with the European Union directive 2004/108/EC on electromagnetic compatibility, and with the IEC international regulations. The unit has been designed and manufactured for use in industrial areas, in accordance with EMC standards. This compliance results from a test performed according to article 10 of the directive, and included in protocol CE- 26/08-43-EE-1. Page 27 of 84

28 GENERAL INSTRUCTIONS FOR IG-159-GB 7. PROTECTION, METERING AND CONTROL MODELS 7.1. DESCRIPTION OF MODELS vs. FUNCTIONS T Distribution transformer protection unit installed in fuse-combination switch cubicles. The electronic unit performs all the protection functions except for the high value polyphase short-circuits that occur in the transformer s primary. It has inputs and outputs for switch monitoring and control. The unit can protect a power range from 50 kva up to 2000 kva in CGMCOSMOS system cubicles and from 50 kva up to 1250 kva in CGM-CGC and CGM.3 system cubicles. G Distribution general protection unit installed in circuit-breaker cubicles. The main usage applications are: general protection of lines, private installations, transformers, capacitor stacks, etc. They can protect a power range from 50 kva up to 400 kva (630 kva for CGM-CGC and CGM.3 system cubicles), when they include toroidal-core current transformers from 5 A to 100 A. With 15 A to 630 A toroidal-core current transformers, they offer a power range between 160 kva and 15 MVA (25 MVA for CGM-CGC and CGM.3 system cubicles). Page 28 of 84

29 84 GENERAL INSTRUCTIONS FOR Protection, Metering and Control Units T G General Phase current sensors 3 3 Earth (zero-sequence) current sensor Op Op Voltage sensors No No Digital Inputs 2 2 Digital outputs 2 2 Power supply 24 V dc to 125 V dc / 24 V ac to 110 V ac Op Op Self powered (> 5 A, V ac +/- 30%) Op Op Protection Phase overcurrent (50-51) Yes Yes Earth leakage overcurrent (50N-51N) Op Op Ultrasensitive earth leakage protection (50Ns-51Ns) Op Op Thermometer (49T) Yes Yes Communications MODBUS-RTU Yes Yes PROCOME No No RS-232 configuration port Yes Yes RS-485 port for remote control Yes Yes ekorsoft setup and monitoring program Op Op Indications Tripping cause indication Yes Yes Error display Yes Yes Test Test blocks for current injection Yes Yes Output contact for test Yes Yes Measurements Current Yes Yes Presence / Absence of voltage No No Op - Optional Page 29 of 84

30 GENERAL INSTRUCTIONS FOR IG-159-GB 7.2. RELAY CONFIGURATOR NOTE Not all combinations resulting from this configurator are possible. For the availability of other models, please consult Ormazabal's Technical - Commercial Department. To select the unit on the basis of the installation characteristics, the following configurator will be used: Type: G For protection cubicle with circuit-breaker T For fuse protection cubicle Protection functions: 10 Three phases (3 x 50/51) 20 Three phases and neutral (3 x 50/ N/51N) 30 Three phases and sensitive neutral (3 x 50/ Ns/51Ns) Toroidal-core current transformers: 0 Without toruses 1 Range A 2 Range A Power supply: A Self powered B Auxiliary power supply (Battery, UPS, etc.) Example: In the case of a selfpowered relay for a protection cubicle with a circuit-breaker, with functions 3 x 50/ Ns/51Ns and toroidal-core current transformers with a range of A, the corresponding configurator would be G-301A. Page 30 of 84

31 84 GENERAL INSTRUCTIONS FOR 7.3. T UNITS Functional description The T protection, metering and control unit is used for the protection of distribution transformers. It is installed in fuse-combination switch cubicles so the electronic system performs all the protection functions, except high polyphase short-circuit values, which are cleared by the fuses. When an overcurrent that is within the values that the load break switch can open is detected, the relay acts upon a low power bistable trigger that opens the switch. If the fault current is greater than the breaking capacity of the load break switch [2], the switch trip is blocked so that the fuses will blow. On the other hand, the equipment is disconnected and the fuses do not remain energised. TRANSFORMER PROTECTION GENERAL PROTECTION (MV client supply) [2 ] 1200 A for CGMCOSMOS-P, 480 A for CGM-CMP-F, 36 kv range, and CGM.3 and 300 A for CGM-CMP-F, 24 kv range. Page 31 of 84

32 GENERAL INSTRUCTIONS FOR IG-159-GB Technical Characteristics The T unit is used to protect the following transformer power ratings. Line voltage Fuse Rated Voltage [kv] CGMCOSMOS System MINIMUM Transformer Power Fuse Rating [A] [kva] MAXIMUM Transformer Power Fuse Rating [A] [kva] [kv] 6,6 3/7, ( ¹ ) / ( ¹ ) ,8 10/ / ( ² ) / ( ¹ ) 442 mm cartridge, ( ² ) 125 A SIBA SSK Fuse Line voltage Fuse Rated Voltage [kv] CGM-CGC / CGM.3 System MINIMUM Transformer Power MAXIMUM Transformer Power Fuse Rating [A] [kva] Fuse Rating [A] [kva] [kv] 6,6 3/7, ( ¹ ) / ,8 10/ / / / (2) / (2) 2500 ( ¹ ) 442 mm cartridge (2) SIBA SSK fuse (check) Selection process for the T unit protection parameters in CGMCOSMOS-P cubicles: 1. Determine the required fuse rating to protect the transformer in accordance with the fuse table in Ormazabal s document IG-078. The maximum ratings that can be used are 160 A for voltages up to and including 12 kv, and 125 A for voltages up to and including 24 kv. 2. Calculate the transformer rated current I n = S/ 3xU n. 3. Define the continuous overload level I>. Normal values in transformers of up to 2000 kva are 20% for distribution installations and 5% for power generation installations. 4. Select the transitory overload curve. Coordination between relay curves and LV fuses is performed with the EI type curve. 5. Define the delay time in transitory overload K. This parameter is defined by the transformer s thermal constant. This way, the greater the constant, the longer it takes for the transformer s temperature to increase under an overload condition; and therefore, the protection trigger can be delayed longer. The usual value for distribution transformers is K = 0.2, which means that it trips in 2 s if the overload is 300% in the EI curve. 6. Short-circuit level I>>. The maximum value of the transformer s magnetisation current must be determined. The current peak produced when a no-load transformer is connected, due to the effect of a magnetised nucleus, is several times greater than the rated current. This peak value, up to 12 times the rated value (10 times for more than Page 32 of 84

33 84 GENERAL INSTRUCTIONS FOR 1000 kva) has a very high harmonic content, so its fundamental 50 Hz component is much less. Therefore, a usual setting value for this parameter is between 7 and Instantaneous time delay T>>. This value corresponds with the protection trip time in the event a short-circuit occurs. It depends on the coordination with other protections and the usual values are between 0.1 and 0.5 s. If the short-circuit value is high, the fuses will act in the time determined by their characteristic curve. 8. Determine the current value in case of secondary three-phase short-circuit. This fault must be cleared by the fuses, and it corresponds with the intersection point s maximum value between the relay and the fuse curves. If the intersection point is greater than the secondary short-circuit value, the settings must be adjusted to meet this requirement. To select the T unit protection parameters in CGM-CMP-F and CGM.3-P cubicles, the steps to follow are similar to those proposed in the paragraphs above, except for the first step. The fuse rating required to protect the transformer is determined according to the fuse table of Ormazabal s documents IG-034 and IG-136 respectively. Please take into consideration that the minimum protection powers are listed in the table above. In case of protecting a transformer with following characteristics in CGMCOSMOS cubicle system: S = 1250 kva, U n =15 kv and U k = 5% Follow the procedure below for proper coordination between the fuses and the protection relay: Fuse selection according to IG /24 kv 125 A fuse Rated current. In = S/ 3 x U n = 1250 kva/ 3 x 15 kv 48 A Continuous withstand overload 20%. I n x I> = 48 A x A Extremely Inverse Curve type. E.I. Transitory overload factor. K =0.2 Short-circuit level. I n x I> x I>> = 48 A x 1.2 x A Instantaneous time delay T>> = 0,4 s Secondary short-circuit. I cs = I n x 100/ U k = 48 A x 100 / A Page 33 of 84

34 GENERAL INSTRUCTIONS FOR IG-159-GB Figure 7.1: Example for SIBA SSK fuse The earth unit setting depends on the characteristics of the line where the unit is installed. In general, the earth fault values are high enough to be detected as overcurrent. Even in isolated or resonant earthed neutral networks, the fault value in transformer protection installations is clearly different from the capacitive currents of the lines. This way, the transformer protection T units are used in isolated neutral networks that do not require the directional function. The values of the setting parameters must guarantee selectivity with the main switch protections. Given the variety of protection criteria and types of neutral used in the networks, it does not exist a single parameterisation; each case requires a specific parameterisation. For transformers up to 2000 kva, the settings below are given as a general example. It must be ensured that they properly apply to the protections upstream (general, line or main switch protections, among others.) Page 34 of 84

35 84 GENERAL INSTRUCTIONS FOR Phase setting Setting of Earth Rated Current Time delayed Instantaneou s I> K I>> T>> In=S/ 3xU n = 48 A EI DT 1,2 0,2 7 0,4 Type of Neutral Time delayed Instantaneou s I o > K o I o >> T o >> Solid or impedant NI DT 0,2 0,2 5 0,4 Isolated or resonant NI DT 0.1/Ig=2 A(*) 0,2 5 0,4 ( * ) In case a zero-sequence toroidal transformer is used Page 35 of 84

36 GENERAL INSTRUCTIONS FOR IG-159-GB Installation in a Cubicle The integral parts of the T units are the electronic relay, the power supply and test board, the bistable trigger and the current sensors. The electronic relay is fixed to the cubicle driving mechanism using anchors. The front of the equipment, which contains the components of the user interface, display, keys, communication ports, etc., is accessible from the outside without the need to remove the mechanism enclosure. The rear contains the X1 and X2 connectors, as well as the wiring that connects it to the power supply board.. CGM.3-F Page 36 of 84

37 84 GENERAL INSTRUCTIONS FOR All of the signals that come from the relay go through the board. Hence, the board enables the unit to be checked. Furthermore, there is a volt-free contact (J3) which is activated simultaneously with the relay trip. This enables to use conventional current injection equipment for testing the protection relays. The selfpowered transformers are also connected to the power supply board using the J7 connector in the selfpowered relays. The signal transformers are connected to the board's J8 connector, the function being to inject current into the secondary in order to test the relay. The T protection, metering and control unit has three connectors (J1, J3 and J4) to which the user can connect. They are situated on the upper part of the power supply and test board and their functions are as follows: Connector Name Functions Normal use It must be connected to an NO, volt-free J1 EXT. TRIP contact. When it is activated, the protection Transformer THERMOMETER. device trips if an overcurrent protection function is activated. J3 TRIP This is an NO, volt-free contact which is Protection unit TEST. activated when the protection device is Trip SIGNAL for remotelycontrolled tripped. It also works in self powered mode. installations J4 V. AUX Auxiliary power supply input: 230 V ac for selfpowered units and 24 to 125 V dc or 24 to 110 V ac for those with auxiliary power supply (10 kv insulated in relation to the rest of the equipment, in self powered models). Relay power supply (LVB of the transformer to protect, battery, etc.). Page 37 of 84

38 GENERAL INSTRUCTIONS FOR IG-159-GB T Electrical Diagram NOTE For more details, please see electrical diagram No , which shows the electrical connections between the different parts of the G unit and the cubicle. Page 38 of 84

39 84 GENERAL INSTRUCTIONS FOR Installation of Toroidal-core current transformers The installation of toroidal-core current transformers requires special attention. It is the main cause of untimely tripping problems, and its improper operation can cause trips that go undetected during commissioning. Aspects that must be considered in the installation: The toroidal-core current transformers are installed on the outgoing cables of the cubicle. The inner diameter is 82 mm, which means that MV cables can easily pass through the inside. The earthing screen MUST go through the toroidal-core current transformer when it comes out of the part of cable remaining above the toroidal-core current transformer. In this case, the braided pair goes through the inside of the toroidal-core current transformer before it is connected to the earthing of the cubicle. The braided pair must not touch any metal part, such as the cable support or other areas of the cable compartment, before it is connected to the cubicle's earth. Earth screen: it must pass through the inside of the toroidal-core The earthing screen must NOT go through the toroidal-core current transformer when it comes out of the part of cable remaining under the toroidal-core current transformer. In this case, the braided pair is connected directly to the earthing collector of the cubicle. If there is no braided pair for the earthing screen because it is connected at the other end (as in metering cubicles), the twisted pair should also not go through the toroidal-core current transformer Checking and Maintenance The T protection, metering and control unit is designed to perform the operating test necessary for both commissioning and regular maintenance checks. Several levels of checks are available depending on the possibility of interrupting service and accessing the MV cubicle cable compartment. Check through the primary: This case corresponds to the tests that are performed on the equipment when it is completely shut down, since it involves actuating the switchdisconnector and earthing the cubicle outgoing cables. When current is injected through the toroidal-core current transformers, you must check that the protection opens the switch within the selected time. In addition, you must make sure that the tripping indications are correct and that all the events are being recorded in the history log. CAUTION To perform this check, the unit must be powered up. Hence more than 5 A must be injected, or it must be connected to 230 Vac for self powered relays. As regards those which have auxiliary power supply, feed the voltage through the board's J4 connector. Page 39 of 84

40 GENERAL INSTRUCTIONS FOR IG-159-GB To perform this check, follow the steps indicated below: - Open the cubicle s switch-disconnector and then earth the output. - Access the cable compartment and pass a test cable through the toroidal-core current transformers. - Connect the test cable to the current circuit of the tester. - Connect the power supply board's J3 connector to the tester's timer stopper input. - Open the earthing switch and close the switch. Reset the latch and remove the actuating lever in order to leave the cubicle ready for tripping. - Inject the test currents and verify the tripping times are correct. Check that the trips are correctly displayed. For phase trips, the test cable must pass through two toroidal-core current transformers. The cable must pass through each of them in opposite direction; in other words, if in the first one current flows up bottom, in the other it must flow bottom up so that the sum of the two currents equals zero and no earth trip occur. For earth trips, the test cable is passed through a single toroidal-core current transformer (zero-sequence or phase toroidal, depending on whether a zero-sequence toroidal is available or not). Trip tests must be performed for all toroidal-core current transformers to check the proper operation of the complete unit. Check through the secondary. In this case, the tests are performed on the equipment when the cable compartment is not accessible. This occurs because the cubicle outgoing cables are energised and cannot be connected to earth. In this case, it is not possible to feed a test cable through the toroidal transformers and current must be injected from the power supply board. This testing method is much better than using testing equipment (normally more than 100 A). To perform this check, follow the steps indicated below: - Access the control's upper compartment where the power supply board is located. - Disconnect the bistable trigger. - Disconnect the blue, brown, black and earth cables of the J8 connector, corresponding to points J8-6, J8-8, J8-10 and J8-1 respectively. - Connect the previously disconnected cables to the earth points N of connector J8-3. This operation will short-circuit the current transformers' secondary circuitry. Page 40 of 84