Control Box Assembly (Front) - Hobart Jet-Ex 5D Operation And Maintenance Manual

OM-2094 / Operation and Maintenance Manual
Jet-Ex 5D / Series 500285 / Generator Set
g. Control Box Assembly (Front) (Figure 5)
The Control Box Assembly (Figure 5) houses and provides mounting facilities for controls,
monitoring instruments, voltage regulator, relays, etc. The box is mounted at the rear of the
canopy. Its control are accessible behind a hinged plastic cover.
(1) TACHOMETER (M403)
This instrument receives its operating signal from the alternator to display the engine speed in
RPM.
(2) HOUR METER (M402)
The HOUR METER records the total hours of engine operation for scheduling maintenance.
(3) VOLT METER, generator (M406)
The VOLT METER indicates generator output voltage.
(4) AMMETER (M407)
The AMMETER displays generator current output.
(5) PANEL LIGHTS FUSE (F401)
This protects the panel lights circuit.
(6) PANEL/CLEARANCE LIGHTS toggle switch (S405)
The PANEL/CLEARANCE LIGHTS toggle switch turns the panel and clearance lamps on and
off.
(7) CONTACTOR CONTROL toggle switch (S408)
The CONTACTOR CONTROL toggle switch is a three-position toggle switch used to close and
open the output load contactor. The top CLOSE position is spring-loaded and is held
momentarily until the CONTACTOR CLOSED lamp (8) glows, then it is released to the center
ON position. In this position the switch provides holding current to the load contactor to keep it
closed. Protective devices in the load contactor circuit provide protection against over voltage by
opening the load contactor if that condition occurs. In the bottom OFF position, the contactor is
opened.
(8) CONTACTOR CLOSED lamp (DS408)
The CONTACTOR CLOSED lamp glows green when the output load contactor is closed.
(9) CURRENT LIMITING CONTROL POTENTIOMETER (R402)
The CURRENT LIMITING CONTROL POTENTIOMETER is used to select the starting current
recommended for various aircraft. The current limiting setting is continuously adjustable from
300 to 2000 amperes.
(10) SPEED CONTROL toggle switch (S406)
The SPEED CONTROL toggle switch is a two position switch wired to a throttle solenoid on the
engine. In the IDLE position, used for starting, the engine speed is controlled to approximately
1000 RPM. In the Rated RPM position, engine speed is controlled to approximately 2500 RPM.
(11) ENGINE ON lamp (DS407)
The ENGINE ON lamp glows green when the engine is running.
November 1, 2000
Revised 07/01
Chapter 1-1
Page 11