Table of Contents
Advertisement
MODEL 220
HYDRAULIC
IMPACT HAMMER
VI.
ELECTRICAL CIRCUITRY
A. DIESEL ENGINE
The BATTERY provides 24 volt current to start the diesel engine.
FORWARD-REVERSE switch turned to OFF, turning the ENGINE START SWITCH
to START energizes the START RELAY which energizes the START MOTOR and
turns over the diesel engine. If fuel is available, the diesel engine will start. In order
for fuel to be available to the engine, the SHUTDOWN RESET must be closed to
energize the FUEL SOLENOID. The FUEL SOLENOID opens the fuel rack and
allows fuel to flow to the engine. With the diesel engine running, the AMMETER
indicates charging amperes. The HOUR METER indicates engine operating hours.
The MAIN POWER (CB2) switch, when in the ON position, provides electrical
power to the balance of the power unit and hammer controls. The MAIN POWER
switch is also a circuit breaker, providing over current protection to the electrical
system.
Turning the MAIN POWER switch to the OFF position disables the
pendant and power unit controls. Turning OFF the MAIN POWER switch DOES
NOT disable the safety shut down system (SHUTDOWN RESET) or the engine
HOUR METER.
A system of safety controls shuts off the fuel supply, thereby stopping the diesel
engine, in the event that engine water temperature is too high or engine oil pressure
is too low. The heart of the safety system is the SHUTDOWN RESET which is
normally closed, thereby providing current to operate the HOUR METER and to
energize the fuel rack and allows fuel to flow to the diesel engine.
SHUTDOWN RESET must remain closed so that fuel continues to flow to the diesel
engine.
If the coil in the SHUTDOWN RESET is momentarily energized, the SHUTDOWN
RESET will open shutting off the fuel to the diesel engine. The engine will stop.
The coil may be energized by any one of the following devices:
1. Engine Oil Pressure Gage - If oil pressure is below 15 PSI (1 Bar), the contacts
of the gage will be closed providing current to energize the coil. On start-up, the
reset button of the SHUTDOWN RESET (on the control panel) must be held
until 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 SHUTDOWN RESET coil.
3. Emergency Stop: - Pressing the emergency stop button, on the remote pendant,
will energize the SHUTDOWN RESET coil.
The diesel engine is stopped by turning the ENGINE START SWITCH to OFF. This
will de-energize the FUEL SOLENOID shutting off the fuel to the engine. Turning
the ENGINE START SWITCH to OFF also disconnects all other electrical circuits.
VI-1
With the
The
Advertisement
Table of Contents
