CONTROL PANEL (TYPE 2)
SYSTEMS OPERATION
Return of Commercial (Normal) Power
When commercial power returns, the automatic
transfer switch transfers the load to commercial power.
Initiating contacts (I) open. This de-energizes run relay
(RR) and arming relay (AR).
When run relay (RR) is de-energized, contacts
(RR2) close and contacts (RR1) open. (RR2) closed
energizes rack solenoid (RS). The rack solenoid moves
the rack to the FUEL OFF position. (RRI) open prevents
an indication of low oil pressure with normal shutdown.
When arming relay (AR) is de-energized, contacts
(AR1 and AR2) open and contacts (AR3 and AR4) close.
(AR1) open prevents the arming relay from being
energized before the engine starts. (AR2) open
prevents current flow to rack solenoid (RS) when engine
control switch (ACS) is in the OFF or STOP position.
(AR3) closed helps complete the circuit to magnetic
switch (MS). (AR4) closed helps complete the circuit to
and overcrank timer (OCT).
When the engine stops, pressure switch (PSW)
opens. This de-energizes water temperature gauge
(WTG), oil pressure gauge (OPG) and rack solenoid
(RS).
Diode (D1) releases any voltage in the coil of rack
solenoid (RS) when it is de-energized.
CONTROL PANEL WITH ELECTRONIC SPEED SWITCH
AUTOMATIC POSITION-COMMERCIAL POWER RETURNS
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