The Company And Its Products

Transcript

The Company and its Products GEC ALSTHOM T&D Protection & Control Limited is part of GEC ALSTHOM, one of the largest electrical power generation, transmission and distribution groups in the world. It is an acknowledged world leader in the design and production of relays and instrumentation. This position has been achieved through a continuing policy of increasing investment in new product development. The company is represented all over the world and has its British base at Stafford where approximately 1,600 personnel are employed. GEC ALSTHOM T&D Protection & Control markets a quality range of electrical instrumentation serving the control requirements of the power generation, transmission, distribution and industrial process markets. This product range includes: ● Panel instruments (conforming to DIN, BS and ANSI standards) ● Istat electrical transducers ● MotorMaster motor protection relays ● Novar capacitor controllers ● R30 Chart recorders ● Battery alarms ● Rotary switches ● Prima Auxiliary Relays Expert technical support for product selection, application and after sales service is available through a network of over 80 established representatives around the world. 2 Substation battery installations are required to provide not only dc auxiliary supplies for protection and control equipment, but also to supply trip and close currents to breakers under tripping conditions. Monitoring of the performance of the dc system is therefore fundamental to the efficient operation of the substation. Battery Alarm 300 is designed to provide comprehensive continuous battery monitoring and to give local and remote indication of alarm conditions, including an impedance alarm. This alarm is designed to monitor the ability of the battery to supply a large current for trip/close requirements, failure of which could result in extensive damage. Early detection of such problems using Battery Alarm 300 allows effective maintenance to be scheduled to help maintain the integrity of the dc system. Product Features Customer Benefits ● Monitors ability of battery to supply load current ● Ensures dc powered equipment such as critical protection relays and SCADA systems remain operative ● Provides continuous in-service monitoring of the battery ● The need for time consuming and costly site visits and battery servicing by maintenance engineers is minimized Batteries may remain safely in service after perceived useful life has expired, thus reducing replacement costs ● Over and Under voltage alarms ● Ensures battery charge is sufficient to support the required voltage level Ensures battery charger is performing correctly ● High Impedance alarm ● Guards against high battery circuit impedance, caused by corroded terminals or internal build-up of plate deposits, which would prevent the battery from supplying the required load current Improves security of remote unmanned installations against theft ● Earth Fault alarm ● Protects against earth leakage which could prevent the battery supplying sufficient load current and would also result in increased charging costs ● Fault indication LEDs and relay contacts ● Local and remote alarms to facilitate fast and efficient fault diagnosis ● Models available for each of seven standard dc voltages up to 220V dc ● Security of supply available for all dc powered equipment ● Wide voltage alarm setting ranges ● Suitable for all types of battery including lead-acid and alkaline ● Loss of supply volts indicated via drop-off of normally energized relay, providing self checking ● Battery Alarm does not require expensive maintenance ● Self-powered with minimal burden ● Easily retrofitted to existing installations 3 Application Battery Alarm 300 has been designed specifically for electrical substation batteries and has become a standard for many utilities both for new installations and for retro-fit to existing batteries. It is suitable for all batteries with an internal impedance exceeding 0.1Ω. For battery charger systems fitted with capacitor filtered outputs, the Battery Alarm requires a choke of >2 mH to be fitted at the output of the battery charger to ensure correct operation of the high impedance alarm (see Figure 1). Warnings Caution. Refer to the Operation & Maintenance Manual (I9-100) before installing, commissioning or operating the equipment. 1 2 Installation, commissioning and maintenance should only be carried out by qualified personnel. Battery charger systems with an inductive output element only, should have a suitable load connected, such as a battery, during commissioning and normal operation. This is to avoid resonance of the output inductor with the system capacitance which may produce damaging high peak output voltages. 3 Terminations exposed during installation and maintenance may present a hazard unless the equipment is electrically isolated. 4 The equipment should only be operated as intended e.g. with covers in place and the earth conductor connected to maintain the incorporated safety features. 4 Optional choke (Required when battery charger has capacitor filtered output) FS1 Battery Urgent E FS2 Busbars to battery loads 2A rating Non-urgent Charger For substations it is important that the security of the supply is maintained. This means not only that the battery voltage is within required limits, but that earth leakage and any latent faults in the battery and connections will not result in failure to initiate tripping when a heavy current is demanded. For external wiring diagram see Figure 1. 3 1 2 6 4 5 8 7 9 11 10 12 To telemetry 2A rating Note: The Battery Alarm is shown in the energised state. Under healthy operating conditions the urgent relay is operated and the non-urgent relay is released. Figure 1: External wiring diagram Description ● Power supply operative ● Earth fault positive The Battery Alarm is designed for flush panel mounting and connection to the battery bus wiring. This forms the source of supply for the electronics and also enables the device to monitor battery performance. The outputs provided are volt free contacts from two separate relays. The first, designated URGENT, is normally energized and will de-energize if the monitored parameters deviate beyond preset limits. The second relay, designated NON-URGENT, is normally de-energized and will energize if the monitored parameters deviate beyond preset limits. Each relay channel is fitted with a preset timer which serves to inhibit alarms of a transient nature. Each relay can be configured to monitor any, or all, of the battery parameters. Two sets of changeover contacts are available on each relay. A version is available with both relays designated NON-URGENT. Both relays are normally de-energised and will energise if the monitored parameters deviate beyond preset limits. The unit has six LED indicators so that fault recognition is possible in the event of a sustained fault. These indicators display: ● Earth fault negative ● High impedance ● Over voltage ● Under voltage The window and front panel are cut away to provide easy access to three circuit adjustment potentiometers for setting-up the following: ● High impedance trip level ● Over voltage alarm point ● Under voltage alarm point High impedance alarm The high impedance alarm circuit monitors the ability of the battery, together with the charger and associated wiring, to provide a heavy current pulse. The impedance monitoring circuit operates by drawing a series of heavy current pulses (approx. 1A) from the battery busbars. The values of these pulses are stored and, if a succession of pulses is low, the alarm will operate. The circuit is driven by a low frequency oscillator which gives a pulse rate of two per second. The pulse duration is approximately 50 microseconds. The high impedance monitoring circuit can be adjusted to monitor battery impedances in the range of 0.1Ω to 5Ω. It should be noted that the resistance of the fuses and connecting cables will have an effect on the potentiometer setting. Fuses should be rated at 2A and all wiring should be kept as short and direct as possible. Voltage alarm level settings The voltage levels specified will depend on the operating conditions of the battery installation and the purpose for which the alarms are required. However, the working voltage range of the Battery Alarm must be taken into account when deciding on a specification. The Battery Alarm power supply can accommodate a maximum variation of 80…140% in the input from the battery. The power supply is generally designed to operate over a voltage range from maximum boost voltage down to a minimum voltage below which a battery would not normally be allowed to deteriorate. The over and under voltage alarm settings must be within this range. The adjacent figures can be used as a guide to suitable settings. High voltage cut-off facility A high voltage cut-off facility is achieved by routing the over voltage alarm through the NON-URGENT relay with a short time delay setting eg. 2s and also through the URGENT relay with a longer time setting eg. 50s. This provides a means of switching off the charger or performing other switching operations on detection of a high voltage alarm condition. A similar low voltage cut-off version can also be provided. Parameter (per cell) Lead acid Alkaline Nominal volts 2.00 1.20 Max volts on boost 2.60 1.68 Working volts on charge 2.27 1.46 Minimum volts 1.85 1.00 Low alarm operation 2.14 1.32 High alarm operation 2.40 1.52 For example: For a 55-cell lead acid battery Low alarm setting = 55 x 2.14 = 117.7V High alarm setting = 55 x 2.40 = 132V The over and under voltage alarm levels are adjustable (see technical specification). Note The over and under voltage alarms have built-in hysteresis to prevent contact chatter. This hysteresis (or pick up/drop off differential) will result in a high alarm reset voltage of (0.995 x Vtrip) ±0.5% and a low alarm reset voltage of (1.005 x Vtrip) ±0.5%. Earth fault alarm The earth terminal on the Battery Alarm is connected to the case back plate and also to the earth fault circuit input. A leakage path from either the positive or the negative pole of the battery to earth will cause a current to flow in the input to the earth fault circuit. If this current exceeds a predetermined value, the earth fault relay will operate and the relevant LED will illuminate. The earth fault trip level is preset within the range 5…90kΩ and is symmetrical for both positive and negative earth faults, irrespective of battery voltage. If either the positive or negative of the battery is earthed, the Battery Alarm 300 will indicate an earth fault alarm. In the case when an earth fault relay is already fitted, then a Battery Alarm 300 model without earth fault is recommended. Alarm indications and relay outputs A popular configuration for alarm relay outputs is: – URGENT alarm for over voltage, under voltage and high impedance; – NON-URGENT alarm for earth faults. On detection of an over voltage, under voltage or high impedance fault, the associated panel LED will light immediately. At this stage the urgent alarm delay will start to time out and, if the fault persists, the urgent alarm relay will release after the delay time. On detection of an earth fault, the associated panel LED will light and the NON-URGENT delay timer (usually 1s for earth faults) will start. The NON-URGENT relay will pick-up when the timer times-out. Each relay channel is fitted with a timer and each channel can be configured to monitor any of the battery parameters. Both relays have two sets of volt-free changeover contacts which can be used for local and remote alarms, SCADA inputs etc. 5 Technical Specifications Battery Voltage Ranges Battery voltages (VB) Operating Range Burden Voltage alarm levels (adjustable) Under voltage range Over voltage range Accuracy of setting Hysteresis on setting Earth leakage protection (preset) Trip level range Accuracy of trip level Hysteresis on trip level Short circuit current High impedance alarm (adjustable) Setting range Accuracy of setting Hysteresis on setting 24V, 30V, 32V, 48V, 50V, 60V, 110V, 125V, 220V. 80…140%VB 20mA nominal 80…110%VB 105…140%VB ±0.5% 0.5% 5kΩ to 90kΩ ±10% 5% <5mA 0.1Ω …5.0Ω ±0.05Ω 0.05Ω Temperature Nominal range of use Reference temperature Temperature coefficient Voltage alarms Earth leakage alarm Timer settings High impedance alarm –20°…+60°C 23°C ±0.006%/°C ±0.06%/°C ±0.06%/°C <0.1Ω deviation in setting over temperature range Electromagnetic Compatibility Directive 89/336/EEC Emissions standard EN50081-2 1994 Industrial environment Immunity standard EN50082-2 1995 Industrial environment (IEC801 parts 2, 3 and 4) Susceptibility to Electrostatic Discharge 8kV air discharge/4kV contact. WARNING: This specification applies when the front cover is fitted. If the front cover is removed to gain access to the adjustment potentiometers then appropriate ESD protection must be taken. Low Voltage Directive 72/23/EEC Designed to EN61010-1 1993 safety requirements. Timers Alarm time delay settings Accuracy of setting 1, 2, 4, 8, 16, 32, 64, 128s (other settings available on request) ±10% (±0.25s) Output relays URGENT alarm relay NON-URGENT alarm relay 2 changeover contacts 2 changeover contacts Contact ratings Max. switching power Max. switching voltage Max. switching current 6 60W; 62.5VA 220V DC; 250V AC 2A Max. carrying current Isolation Insulation resistance 3A 750Vrms across open contacts >100MΩ at 500V DC Miscellaneous Series mode noise (ripple) Common mode noise 10%VB(pk-pk) 50…120Hz 100Vrms 45…65Hz Isolation 1kVrms between inputs and alarm contacts 5kV (1.2/50µs) to IEC60-1/BS923 and IEC255-5/BS5992-3 To IEC255-22-1/BS142 Section 1.5.1 2 x VB continuous or 200V dc whichever is lower 350V dc continuous 0…93% +2% –3% RH Barrier type M3.5 Impulse High frequency disturbance Overload ratings 220V version Humidity Terminals LED indications Power on Earth fault (positive) Earth fault (negative) High impedance Over voltage Under voltage Green LED Red LED Red LED Red LED Red LED Red LED Fail to safety and power on reset of URGENT alarm relay. If the supply voltage falls below 66%VB for longer than 50ms, an instantaneous URGENT alarm is given. When the supply voltage returns to above 66%VB, a power on reset occurs after a time delay of 1 second. Information required with order Nominal battery voltage Battery type (eg lead acid, nickel cadmium, etc.) Number of cells High and low voltage alarm points Earth fault trip level Relay alarm designations (if different from configuration shown on page 5) Alarm time delays Outline dimensions 96 5 104 24 96 Panel cut-out 92 +0.8 –0 square (Dimensions in mm) 7