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CHAPTER 1 GENERAL INFORMATION AND OPERATING INSTRUCTIONS
NMC-WOLLARD
2021 Truax Blvd. Eau Claire, WI 54703 ● P: 715-835-3151● F: 715-835-6625 ● www.nmc-wollard.com
TML-704H Maintenance Lift Manual No. 310547
1 DESCRIPTION
When the keyswitch is turned to "O", diode REC 1 blocks any reverse ow of
current from the alternator and prevents the fuel solenoid from being held in
by a backfeed of current through the resistor/light circuit.
Indicators and Hourmeter
Lights on the control panel monitor oil pressure, water temperature, brake
fault, remote switch o, retract stabilizer, parking brake on, and low voltage
conditions. A digital hourmeter is mounted below the panel and registers
engine running time. A fuel level indicator is located on teh instrument panel.
All indicator lights are automatically tested every time the engine is switched
on or o.
• Electric power is fed to the indicator lights and hourmeter through SW1
contact when key switch is in “RUN” or “START” position.
• Oil pressure and water temperature switches on the engine operate the
“LOW OIL PRESSURE” and “HIGH WATER TEMP” indicators on the
instrument panel when these engine conditions exist.
• The pressure dierential/metering valve on the split brake system contains
a switch that closes and illuminates the “BRAKE FAULT” indicator light if
there is any pressure imbalance in the brake system.
• The hourmeter operates anytime the engine is running to record the total
running time on the engine.
• The electric fuel gauge indicates level of fuel in tank.
• The “HIGH WATER TEMP” and “BRAKE FAULT” indicators are
self-testing, as corresponding switches always stay open unless a fault
condition occurs.
• When the keyswitch is o, capacitors CAP-1 and CAP-2 are not charged.
• As the keyswitch contact closes, power is applied to wire #17, and current
begins to ow through indicator lamps PL3 and PL4 into capacitors to
charge the capacitors up to system voltage. As the capacitors charge
and their voltage rises, the current through the lamps is correspondingly
reduced until the current stops completely. When the key switch is turned
to “RUN”, this is seen as an immediate illumination of the lamps, then a
gradual dimming until they go out.
• When the keyswitch is turned to “OFF”, the voltage supply is removed
from wire #17. The capacitors, which are charged up to system voltage,
then discharge through the lamps and the fuel solenoid back to ground.
This is seen as a momentary illumination of the lamps when the keyswitch
is turned o.
Engine Glow Plug Circuit
Glow plugs are installed in diesel engines to aid in cold weather starting.
Starting procedure is in Cold Weather Diesel Starting.
SEPTEMBER 01, 2015
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