Onan MDJF Series Operator's Manual And Parts Catalog page 14

BATTERY CONNECTION
Battery requires negative ground. Do not attempt to change
batteiy polarity on these sets. Refer to set wiring diagram.
CAUTION
11 the battery is connected to the charging
circuit with the wrong polarity, damage
will occur alter three minutes while stopped or in live
seconds while running. Alternator windings will be damag-
ed almost instantly il battery charging circuit is shorted
belore the resistor.
Refer to set nameplate for battery voltage. For AC
plants with 12 volt system, provide two 6 volt batteries
connected in series (one battery's negative to the other
battery's positive, Figure 9) for 105 amp-hr, 12 volt source.
For AC plants with 32 volt system, provide 32 volt set of
batteries and 200 ampere fused switch, see wiring diagram
for connections.
Connect the battery positive (+) to the starter engaging
solenoid terminal post. Connect the fcattery nega-
tive ( - ) to a good ground on the engine. (Figure 9).
WATER SUPPLY LINE (FIGURE 8)
A continuous supply of cooling water is required. The
water pump inlet is 1/4" pipe thread to 1/2" hose coupling.
Use a section of flexible hose near the set to absorb
vibrations. The inside diameter of the plumbing must be
1/2" or larger. Use permatex or other pipe sealer on all
pipe fittings in supply line to pump. Normally, the pump
should deliver 6 gallons of cooling water per minute.
Measure the discharged water flow after thermostat opens,
to assure the supply line is large enough. Reduce resistance
on pipe runs longer than 5-ft. by using larger inside dia-
meter plumbing. To prove suction line is air tight, see that
no bubbles appear in discharged water. An air leak reduces
lubrication and shortens life of pumps impeller. Install a
strainer in the water suction line inlet and where accessible
for cleaning.
REMOTE START - STOP SWITCH (OPTIONAL)
For re mote control starting and stopping, use 3 wires to
connect the remote switch (SPDT,momentary contact, center-
off type) to the terminal block marked B+, 1, 2, 3, in the
set control box using wire sizes as listed in Figure 9. Pre-
heat circuit requires an extra wire to terminal H and
momentary contact switch (SPST) connection. Remove
jumper between terminals 3 and H before installing remote
wiring.
LOAD WIRE CONNECTIONS (AC)
The set nameplate shows the electrical output rating of the
set in watts, volts and hertz. The set wiring diagram shows
the electrical circuits and connections necessary for the
for the available output voltage. Also see Figure 12.
Meet all applicable electrical code requirements. Work
should be done by a qualified serviceman or electrician
because the installation will be inspected and approved.
The set control box (junction box) has knock out sections
to accommodate load wires. Use flexible conduit and
stranded load wires near the set to absorb vibration. Use
sufficiently large insulated wires. Strip insulation from
wire ends as necessary for clean connections. Connect
each load wire to the proper generator output, lead inside
the set control box. Insulate bare ends of ungrounded
wires. Use a bolt (through the control box) to connect
the grounded ( - i - ) generator lead and load wire. Install
a fused main switch (or circuit breaker) between the gen-
erating set and load (Figure 11). If a test run indicates
wrong rotation of 3 phase motors in the load circuit, switch
the connections at any two generator terminals.
Balance . All Loads: Cunent for any one output load must
not exceed nameplate rating. Overloading can damage
the generator windings. Divide the loads equally between
output leads.
Single Phase Loads on Three Phase Generators: Any
combination of single phase and three phase loading can
be used at the same time as long as the current for any
one output lead does not exceed the generator nameplate
rating.
TO LOAD
GENERATOR
120-V.
FUSE OR CIRCUIT
BREAKER
GROUNDED CURRENT CARRYING CONDUCTOR
UNGROUNDED CURRENT CARRYING CONDUCTOR
THESE LINES FROM
^
DOCKSIDE POWER SOURCE
FIGURE II. DOCKSIDE POWERSOURCE
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