MEC 20 MICROPROCESSOR ENGINE/GENERATOR CONTROLLER
PM047 Rev 13 05/03/30
51
Thomson Technology
9.3.5.2.
UTILITY POWER FAILURE CONDITIONS:
•
Remote Start input signal is activated (i.e. remote start contact closes
when utility power fails, as sensed by utility voltage sensor)
•
Engine starts following expiry of the Engine Start Delay timer (Utility
Ready To Load output stays energized)
•
Once the engine has started and the generator output rises above the
programmed voltage and frequency limits, a warm-up timer is
initiated.
•
Once the warm-up timer expires the Utility Ready to Load output de-
energizes and the NEUTRAL Delay timer is initiated.
•
Once the NEUTRAL DELAY timer expires the Gen Ready to Load
output energizes to signal the transfer switch to transfer to the
generator supply.
Note:
The neutral delay function is only operative
with an electrically-held type transfer switch mechanism (i.e. electrical
contactor type).
9.3.5.3.
UTILITY POWER RETURN:
•
Remote Start input signal is removed and the Return Delay timer is
initiated (i.e. Utility Voltage returns to normal and the Utility voltage
sensor contact opens)
•
Once the Return Delay timer expires, the Generator Ready to Load
output de-energizes and the Neutral Delay timer is initiated.
•
Once the Neutral Delay timer expires the Utility Ready to Load output
energizes to signal the transfer switch to transfer to the utility supply.
Note:
If the generator has a shutdown during the Return or Neutral
Delay periods, the timers are bypassed, and the Utility Ready to Load
output immediately energizes.
•
The generator Cooldown Timer starts timing following expiry of the
Return Delay timer.
•
The generator stops following expiry of the Cooldown Timer.
