±. The addition of a automatic control module allows unattended control of one to four generator sets. The automatic
control module monitors the bus (utility) power source, and controls the starting and sequential loading of one to four
generator sets whenever the bus voltage or frequency fails or deviates from a pre-set value. Only those generators with
the AUTO/MAN selector switch in the AUTO position will be controlled via the automatic control module. The controls
are illustrated in figure 2-19 and described in table 2-6. Reference also Chapter 5 Section IV.
a. Connecting the Automatic Control Module
(1) Change jumper connections as shown in figure 2-20.
(2) Interconnect generator set and automatic control module by wiring supplied J3 connector plug on back of control
cubicle (to be wired by user) on rear of generator control box to TB1 thru TB4 terminal boards in automatic
control module in accordance with FO-15. Connect the load feeder breakers (supplied by user) to the
appropriate control contacts (via TB4). See FO-15 for all interconnection wiring instructions.
LR1, LRTD1 are No. 1 priority feeder controls. They will activate first regardless of which
generator first comes on line. LR energizes instantly, LRTD energizes 2-5 seconds after LR. LR2,
LRTD2 are No. 2 priority feeder controls and will activate only when a second generator comes on
line. Priority No. 3 and No. 4 feeder controls work in a similar manner when generator 3 and 4
come on line. The total load to be supplied to any one load feeder breaker 1 thru 8 shall not
exceed 250 KW.
(3) Set the NO RETURN/TD RETURN/
INSTANT RETURN mode selector switch S1 and the FREQ. SELECT 50 HZ/60 HZ switch S2 to the appropriate or
(4) Connect 120V AC from the line side of the utility breaker to TB1-5 and TB1-6 of the automatic control module.
The neutral wire should be connected to TB1-5.
The over/under voltage relay is normally set for a ± 10% deviation of a L-N voltage of 120V AC. The
over and under frequency relays are normally set for a ± 3% deviation of a bus frequency of either
50 or 60 Hz.
b. ACM Operating Procedure
(1) Manual Operation If manual operation and control of the generators is desired, place the AUTO/TRIP/ MAN
switch (S53) located on the generator set control panel, to MAN position. Place the NO RETURN/TD
RETURN/INSTANT RETURN mode selector switch (S1) located on the ACM, to NO RETURN. The generator
set will not be under control of the ACM and the set controls will be strictly manual via generator control panel.
No relays will be caused to energize or deenergize in the ACM, thereby precluding any effect to the utility
breaker or feeder control relays. If manual paralleling is desired, place the generator set parallel switch to
(2) Automatic Operation If automatic operation is desired, first insure that 120 VAC utility power is available to
ACM by indication of the UTILITY POWER AVAILABLE lamp. Determine which type of automatic power
transfer is desired (instant, time delay or no return) and set