User's Manual

MODEL 66-80 VIBRATORY DRIVER/EXTRACTOR
VI. ELECTRIC CIRCUITRY (Reference:Electrical Schematic Pg VI-5)
A. STARTING DIESEL ENGINE
The engine batteries (EB1, EB2) provide 24-volt current to start the diesel engine.
With the MAIN POWER (CB2) switch on, and holding the SHUTDOWN RESET
button in. Turning the ENGINE START switch to START energizes the start motor
solenoid (SOL) and turns over the diesel engine. If fuel is available, the diesel
engine will start.
B. STOPPING DIESEL ENGINE
Turning the ENGINE START switch to OFF de-energizes the fuel pump RACK
SOLENOID, by de-energizing fuel relay (R3), which shuts off the fuel supply to the
diesel engine. The engine stops.
C. SAFETY CONTROL SYSTEM
A system of safety controls shut off the fuel supply, thereby stopping the diesel
engine in the event that any one of six malfunctions occur. The heart of the safety
system is the SHUTDOWN RESET which is closed during normal operations
(button in), thereby providing current to the fuel relay (R3). With the fuel relay
energized, a set of contacts (R3A) close, energizing the RACK SOLENOID and
turning on the fuel supply. With the SHUTDOWN RESET closed (button in) power
is provided to the vibrator start circuitry.
As mentioned above, the SHUTDOWN RESET is closed during normal operation.
If the SHUTDOWN RESET is opened, the fuel relay (R3) is de-energized, contacts
RA3 open, resulting in the RACK SOLENOID being de-energized thereby shutting
off the fuel supply and stopping the diesel engine. The SHUTDOWN RESET
opens when its timing delay coil (TD,C), or it's "instant trip" coil (C), is energized.
The timing delay or instant trip coil may be energized by any of the following
devices.
1. Engine Oil Pressure Gage - if pressure is below 10 PSI (.7 Bar), the contacts
of the gage will be closed providing current to energize the instant trip coil (C)
and to turn on the indicator light (L1). On start-up, the button on the
SHUTDOWN RESET (on the control panel) must be held in until the oil
pressure exceeds 30 PSI (2 Bar).
2. ENGINE WATER TEMPERATURE GAGE - If water temperature exceeds 210°
F (99°C), the contacts of the gage will close energizing the timing delay coil
(TD,C) and turning on the indicator light (L2).
3. Engine Overspeed Switch - if the engine overspeeds, the overspeed switch will
close, energizing the instant trip coil (C) and turning on indicator light (L3).
VI-1