Foster Cold-Room Technicians Hand Book - Nccvmtc.org

a) Starting Failure: Under power failure condition when MAN/AUTselector is at 2 (AUTO) position, NK releasing operates RH1 (asdetailed earlier at 3c) and also Relay T1 gets supply tooperate. But it actually operate only after the lapse ofpresent time (20 sec) If the engine tried but could not startduring above time, T1 will operate and will release RH1 andhence stops starter (M) and also blocks further start command(If generator starts within the present time of T1 of GK willoperate before the above present time. Then T1 will beprevented from operation and no alarm will come).b) Too low lube oil pressure: If lube oil pressure becomes low(normal) 2.B BAR 40 Psi in the engine while running the oilswitch (P) in the engine will operate which will in turnoperate Relay R2 and Alarm lamp X1 will glow and alsoaudio-alarm will come. R2 operating operates RH2 and T2 andengine will stop detailed earlier at 3c R2 will hold itselfand X1 till it is reset (To reset bring MAN/AUT selectorswitch to 0 position).c) Too High Engine TemperatureThe alarm will stop when the selector is turned to ‘0’position. But in case of above failures (in a & b) it will notactuate again and engine can be tried to start/started afterdue checkup and attention. But in case of high enginetemperature (for engine running for longer period poorventilation etc) engine thermostat will operate and remainclosed till the temperature reduces to required level. Henceturning selector to MAN or AUT position may actuate R2 andX1 again and stop any further starting if the temperature ofthe engine is still high than normal.30