Onan MCCK - CONTROL-O-MATIC DESCRIPTION; CONTROL-O-MATIC OPERATION; CONTROL-O-MATIC OPERATION (Optional)

HIGH TEMPERATURES
1. See that nothing obstructs air flow to and from the
plant.
2. Keep cooling Bystem clean. Maintain water level in
closed system cooling.
3. Keep ignition timing properly adjusted.
LOW TEMPERATURES
1. Use correct SAE oil for temperature conditions. Change
oil only when engine is warm. If an unexpected tem¬
perature drop causes an emergency, move the plant
to a warm location until oil flows freely.
2. Use fresh regular grade (not premium) gasoline. Protect
against moisture condensation. Below 0°F, adjust
main jet fa slightly richer fuel mixture.
3. Keep ignition system clean, properly adjusted, and
the batteries in a well-charged condition.
4. Partially restrict cool air flow, but use care to avoid
overheating.
5. Add good quality anti-freeze if danger of freezing
exists.
DUST AND DIRT
1. Keep plant clean. Keep cooling system clean.
2. Service flame arrester as frequently as necessary.
3. Change crankcase oil every 50 operating hours.
4. Keep oil and gasoline in dust-tight containers.
5. Keep governor linkage clean.
6. Clean generator brushes, clip rings, and commutator;
do not remove normal (dark brown) film. Do not polish.
HIGH ALTITUDE
For operation at altitudes of 2500 feet above sea level,
close carburetor main jet adjustment slightly to maintain
proper air-to-fuel ratio (refer to the Adjustments Section).
CONTROL -0-MATIC
Description
The Control-O-Matic is an automatic control which
performs three functions. It is an engine-control, an
automatic-demand control, and a bilge-blower control,
all contained in one top-mounted control box. The
front panel of this box holds a charge ammeter, an
emergency relay and a 3-position toggle switch.
With the switch in the AUTO position, the Control-O-
Matic will monitor the AC load circuit and:
1. sense a load on the AC line.
2. close the bilge blower circuit (when used), for ap¬
proximately 5 minutes, depending on ambient tem¬
perature.
3. open the bilge blower circuit.
4. start the electric plant.
5. sense when all the load is removed .
6. s top the electric plant.
Operation
When the switch is in the RUN position, the bilge
blower control goes through its control cycle before
the electric plant cranks and starts. With the switch
in AUTO position, the engine will crank and supply
current on load demand after the bilge blower con¬
trol cycles. When the load on the AC line is removed,
the plant will stop. The plant stops when the switch
is moved to the STOP position.
CONTROL-O-MATIC Operation (Optional)
A 3-position toggle switch controls plant operation.
The operator may choose either of two running proce¬
dures.
1. Move switch to RUN position. The bilge blower
control will go through its cycle, the engine will
then crank and start.
2. Move switch to AUTO position. The engine will
start when the load demand circuit senses a need
for current. This occurs after the bilge blower
starts Mid finishes its cycle. The plant will stop
when there is no load on the AC line.
3. Move switch to STOP position. The plant stops.
If stop circuit fails, close fuel valve.
The built-in emergency relay shuts down the plant for
these conditions:
1. Engine fails to start. The engine will crank for ap¬
proximately 90 seconds before the emergency relay
shuts it down.
2. Low oil pressure
3. High water temperature. The engine will stop, start
cranking again for about 90 seconds, then stop, and
not attempt to restart.
To reset the emergency relay, remove the cause of the
emergency, then push the red RESET button on the
Control-O-Matic front panel.
The bilge blower may be connected to the Control-O-
Matic in two ways, Fig. 15 shows the bilge blower
connected to the Control-O-Matic. The blower oper¬
ates from the electric plant cranking batteries. The
B+ and BB terminals are labeled in the Control-O-
Matic Box. With this circuit, the running current of the
blower must not exceed 5 amperes. The user may add
switches as shown to operate bilge blower without
operating the electric plant
In the circuit shown in Fig. 16, an auxiliary relay is
used so that the bilge blower can operate from a sep¬
arate battery or power source. A larger blower may be
15