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The diodes in the alarm circuit are used to isolate the various alarm contacts so that Alarm relay
13CR may be used for more than one function.
E. REMOTE START: The remote start switch or switches are N.O. which close momentarily.
Depressing a remote start switch energizes 8CR which is then locked in through its N.O. contacts
(terminals 6 and 9).
F. DELUGE SWITCH: The deluge switch or switches are N.C. switches, and keep the Deluge relay
14CR energized. Opening a deluge switch contact de-energizes 14CR to allow its N.C. contacts
(terminals 1 and 7) to close and energize 8CR. The remaining sequence of operation is the same as
for a start from water pressure drop described above.
G. POWER FAILURE START (OPTION P): This option automatically starts the engine after a time
delay upon loss of battery charger output. Relay 18CR is held energized by an alarm output of the
battery charger. If the battery charger output should fail, 18CR will drop out and its N.C. contacts
(terminals 1 and 7) will energize 2TR. When 2TR times out its N.O. contacts (terminals 1 and 3)
will close and energize 8CR. The remaining sequence of operation is the same as for a start from
water pressure drop described above.
H. WEEKLY TEST START: The weekly test is initiated by a 7-day Program Clock (PC) operated
from the A.C. line. At the time and day of week programmed, its N.O. contacts close and energize a
Solenoid Drain Valve (SDV) through 6CR and 4CR. The SDV is a three way valve and is connected
in the sensing line to the pressure switch. When it is energized it closes the connection between the
pressure switch and the sensing line and then vents the pressure switch to atmosphere causing the
pressure switch to operate. This, in turn, causes an automatic start as described above. When the
Fuel Solenoid relay 6CR energizes its N.C. contacts (terminals 1 and 7) open and de-energize the
SDV. These contacts also keep the SDV from energizing while the engine is running. The SDV is
open just long enough to drop the pressure and initiate the start sequence.
When the crank relay 7CR energizes, its N.O. contacts (terminals 6 and 9) close to energize 4CR, the
weekly test relay, which locks in on its own N.O. contacts (terminals 4 and 7). 4CR N.C. contacts
(terminal 3 and 9) open to keep 8CR from locking in on those controllers wired for manual stop.
8CR is held energized by the P.C. contacts through diode D51 for the duration of time set on the P.C.
The purpose of the diode D51 is to isolate 4CR contacts from the SDV. When the P.C. contacts
open 4CR drops out, and if all starting causes are normal, 8CR also drops out and the engine stops.
I. Test Start: Switching the controller selector switch to the "Test" position initiates an automatic start
by energizing the solenoid drain valve (SDV) as described above to drop the water pressure to the
pressure switch. The starting sequence is the same as described above. The engine will continue to
run until the selector switch is switched to "Off".
J. Manual Start: The "Man" position of the controller disconnects all automatic start circuits of the
controller and permits manual starting of the engine on either one or both batteries by pressing the
appropriate crank pushbutton(s). All alarms are functional in the "Man" position. The engine will
continue to run until the selector switch is turned to "Off".
K. Additional Features
1. Engine Lockout (Option E): Relay 19CR is an Engine Lockout relay which, when
energized, will keep the engine from starting, or will stop the engine if it is running. This
feature may be used to lock out one pump in a two-pump system, when the other is running,
or to lock out the pump in case of low suction pressure when this is a requirement. The
engine lockout can be overridden by placing the selector switch in "Man" and pressing the
"Manual Crank" buttons.
2. Energize to Stop: This is provided for engines that have a normally open fuel solenoid that
must be closed in order to stop the engine, i.e. Caterpillar engines. With this circuit 1T
Terminal 12 is hot (battery power applied) at all times except while the engine is running.
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