AUTO SYNCHRONIZING AND AUTO LOAD SHARING
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SINGLE LINE DIAGRAM
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When mains are healthy, both the DG¶s remain in the standby mode.
When mains fail, Line Voltage Monitor (L.V.M.) senses. Starting pulses are given to the Master D.G. Set. (Master D.G.Set is automatically selected by programmer.) Af ter satisf actory starting of the D.G.Set 1, voltage is sensed by Generator Voltage Monitor (G.V.M.). If voltage is healthy, then closing signal is given to D.G.1 breaker and it is closed. Synchronizing Panel gives corresponding pulses to start load automatically. The load is then sensed by KW transducer in the panel & continuously monitored by PLC.
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Engine & Alternator parameters are also continuously monitored by P.L.C. in the Panel. In case of any f ault (e.g. Low Lube Oil Pressure, High Cooling Water Temperature etc.), breaker is tripped & engine is stopped. If the load reaches & crosses 80 % of the rated capacity o f the D.G. 1, then starting pulses are given to the second D.G.set by P.L.C. When D.G.2 starts, then again G.V.M. checks the voltage, and if voltage is healthy, then breaker 2 is closed. Af ter closing of the second breaker, Auto load sharing f unction starts sharing the load between the two D.G.Sets. The percentage o f sharing is directly proportional to their individual capacities. Since sharing is proportional to their respective capacities, even D.G.sets of diff erent capacities can be synchronized successf ully. 8/25/2010
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D.G.sets continue to run in Synchronization until the load is above 80 % o f any one D.G. set. When load comes below 80 % o f any one D.G. set, then the automatic signal is given to that D.G. & then it starts taking the f ull load. Af ter transf erring the total load to one D.G. (on which 80 % load is to be connected), the breaker o f the second D.G.is opened. Now one D.G.is taking the load The second D.G. is then stopped af ter its cooling period. When mains are resumed, then load is trans f erred to the mains & both the D.G.sets are stopped af ter their cooling period.
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The total Automatic operation has a manual override. In manual mode, the total operation can be per fo rmed manually. Auto
load shedding f acility can be incorporated by suitable programming of PLC. With this f acility, various loads can be brought in or switched off at particular time or f or various intervals.
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ADVANTAGES OF AUTO SYNCHRONISING & AUTOLOAD SHARING
Changing of logic is very easy because of changes are made through sof tware only. There is no changing of wires, adding of components like relays, contactors, which is very time consuming, cumbersome & requiring additional space. For any type of load addition or reduction, manual intervention as regards D.G.set operation is not required. However, in case o f emergency manual override is possible. Because of KW dependent load sharing, optimum utilization of D.G. sets are possible. This increases D.G. sets eff iciency & saves lot o f f uel. Use of PLC reduces no. of relays, contactors, wiring etc. This reduces f ault points & increases the MTBF of the system. ll the f uture changes / modif ications can be easily made7 A 8/25/2010 through sof tware only.
Automatic Changeover
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Mains source failure
Automatic
Changeover Switch panel is designed to monitor & to start Generator control panel automatically when the mains source f ails partially or f ully. The control panel provides a potentialpotential-f ree contact output & provides signal to the remote generator control panel to enable automatic start of the generator. On sensing that the generator is running at correct output the changeover switch changes over f rom the mains position to generator position, thereby transf erring the site load.
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When Mains restores
L.V.M. checks the mains f or its healthiness, the generator is then disconnected f rom the load and automatic changeover back to the mains source takes place. Load is now connected to the mains. Gen set is then run f or about 5 minutes time set, on no load and it is stopped automatically.
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AMF Panel
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AMF
Control panel is designed to monitor & to start Generator automatically when the mains source f ails partially or f ully. When mains f ail, then it is sensed by Line Voltage Monitor (L.V.M.) and three starting pulses are given to Gen set. If Genset does not start within three attempts, then µSTAR TING FAILUR E¶ alarm is sounded and stop signal is given to Genset to stop it f ully & no start signals are given f urther. When Genset starts successf ully, it builds up the rated voltage and Genset contactor/breaker is closed automatically. The load then is switched on / trans f erred to the Genset. When Mains restores, which is checked by L.V.M. f or its healthiness, the generator is then disconnected f rom the load and automatic trans f er back to the mains source takes 8/25/2010 12 place. Load is now connected to the mains.
Genset is then run f or about 5 minutes time set, on no load and it is stopped automatically. Saf eties like L.L.O.P., H.W.T. and over speed are operative when the Genset is running. For any of the above f aults, Genset stops immediately. Automatic f unction can be totally by by-- passed passed and Genset can be startedstarted-stopped in manual mode also.
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Indication for the following Low oil press High room temp. Over speed Fail to start DC battery REV POLARITY Engine hours run counter RPM Frequency Voltage Current Engine temperature 8/25/2010
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Shutdown Protections
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Low oil press
High room temp
Over speed
Fail to start
Under speed
Over current
V belt failure
Blower failure
Earth fault
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PANEL ACCESSORIES
1 Voltmeter 3- Ammeter 1- Freq. R PM meter Fail to start 1- Battery voltmeter 1-Engine hours run counter 1- Oil press. Gauge 1- Engine temp. gauge 3- C.T. above 100 A
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1- voltmeter sel. Sw 1- Electronic generator control module f ully programmable with : Control key switch Off / R un / Start (OPTION AL) 1- MCB / MCCB 4- AC and DC f uses 1- Control terminals 1- Neutral Neutral terminal 1- Set of AV mounts (OPTIONAL) 2- 20/30 amp rated relays f or f uel and start solenoids
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Kw TRA NSDUCER
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A)
VOLTAGE LEADS Connect the leads to the electrical source to be monitored. B)FUSE C)4-20mA OUTPUT CONNECTOR D) STATUS LED The LED blinks green when the product is f unctioning normally. It will blink slowly, approximately one second on, then one second off . If the LED is red and blinking slowly, it may indicate incorrect wiring or a power f actor that is less than 0.5. If the LED is red and blinking current rating has f ast the CT's maximum been exceeded. E)EXTER NAL CTs 8/25/2010
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OPERATION
Kw TRA NSDUCER combines a microprocessor based kW transducer and high accuracy split-core current transf ormers (CTs) in a single unit. Splitcore design eliminates the need to remove conductors. Three CT versions is used with three phase, unbalanced loads.
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Applications Optimization of chillers, pumps and cooling towers rmance Energy management & per fo contracting
Process control R eal time power monitoring
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