Output Terminals; Contactor; Rectifier Assembly; Ammeter Shunt - Hobart JET-EX 4 Operation And Maintenance Manual

OM-2049
(10) Choke control
The choke control is connected to the carburetor choke butterfly with a flexible control cable. Pull-
ing it out closes and enriches the fuel mixture. Pushing it in opens the choke.
(11) Excitation Rectifiers
Two diode bridge rectifiers, CR418 and CR417, (3, Fig. 5) convert an AC voltage from the gener-
ator armature to the DC voltage needed for the generator revolving field.
(12) Voltage Sensing Relay
Voltage sensing relay K404 (5, Fig. 5) is a safety device which automatically opens the grounding
circuit of the revolving field to prevent excessive voltage build-up if the push-to-build-upvoltage
switch is held in too long, or if it is pushed in after voltage is built up.
E. Output Terminals
The output terminal panel (2, Figure 3) is mounted on the side of the fuel tank support.
F. Contactor
The load contactor which is mounted beside the output terminal panel, provides a safe and conven-
ient means of connecting and disconnecting the generator from the load. Initial power for closing the
load contactor is supplied by the generator through the spring-loaded momentary contacts of the con-
tactor control switch (11, Figure 4). Holding power, to keep the contactor closed, passes through the
normally open auxiliary contacts in the load contactor.
G. Rectifier Assembly
The rectifier assembly (9, Figure 3) is located at the rear of the machine below the control panel. It
consists of two aluminum heat sinks with six diodes on each heat sink. The negative rectifier assem-
bly is mounted nearest to the rear frame and the positive rectifier assembly is mounted nearest to the
generator. The rectifier assembly converts the AC output of the generator to 28.5 V DC.
H. Ammeter Shunt
The ammeter shunt is connected in the generator's negative output circuit. It supplies a small voltage
proportional to output current for operation of the generator ammeter (5, Fig. 4) and for sensing output
current for the current limit circuit of the voltage regulator (1, Fig. 5). This shunt is mounted on a bus
connected to the negative heat sink of the rectifier assembly (9, Fig. 3).
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May 20/89