A R M Y 5 - 6 1 1 5 - 6 1 2 - 3 4
MARINE CORPS TM 6115-34/8
AIR FORCE TO 35C2-3-471-2
N A V Y A G - 3 2 0 B 0 - M M E - 0 0 0
CHAPTER 10
MAINTENANCE OF ENGINE AND GENERATOR CONTROLS AND
INSTRUMENTS
10-1.
PURPOSE AND FUNCTION OF ENGINE discussion of the power supply card is
AND GENERATOR CONTROLS AND INSTRU-
provided separately at the beginning of
MENTS.
This chapter provides informa-
the overall discussion.
The reader
tion to maintain the engine and gen-
should be familiar with the basic
erator controls and instruments at the
theory of
operation
discussed in
direct and general support, and depot
Chapter 4, Section XIV of TM 5-6115-
maintenance
levels.
Included
are
612-12 before reading further.
removal/replacement procedures for the
circuit cards in the EECM, and refer-
(1) Power
supply
card.
FO-9,
ences to applicable paragraphs in TM
sheet 1, is a block diagram of the EECM
5-6115-612-12 covering test and repair
power supply circuit card. This supply
of the control panel.
is an integrated circuit switching
regulator with two sections; one +5 Vdc
a.
Purpose.
The purpose of this
power supply, and one ±12 Vdc power
subsystem is
to
provide
operator
supply.
Prime input power at +24 Vdc
control and monitoring capabilities of
enters the card and is filtered before
both the engine and generator from a
being distributed to other card cir-
single location.
Operator control and
cuits.
The filter output is applied
monitoring of
engine
and generator
across a crowbar circuit to two pass
performance are effected through the transistors, +5 Vdc control circuitry,
controls and indicators on the control
and the +12 Vdc control circuitry. In
panel which are electrically connected
the +5 Vdc control circuit, the +24 Vdc
to the engine electronic control module
is regulated down to a level that
(EECM) and generator electronic control
supplies the pass transistors
suf-
module (GECM).
Circuits within the
ficient drive to provide +5 volts at
EECM provide the actual control and
the pass
transistor
output.
This
monitoring of the engine and generator
voltage is filtered to become the +5
through a microprocessor and associated
Vdc level at the card output that
software.
supplies logic power to the IC devices
in the EECM.
This control circuitry
b. Functional
Theory
of Oper-
also
provides
automatic
overcurrent
ation.
FO-9 is a detailed block
shutdown to the pass transistors should
diagram of the engine and generator
current demand on the +5 Vdc line
controls and instruments.
This theory
exceed a set limit.
In the +12 Vdc
of operation is keyed to the detailed
supply section,
the ±12 Vdc control
block diagram and describes system
circuitry regulates the +24 Vdc prime
operation in sequence from the time
power down to a voltage signal that
power is first applied, through the
supplies drive to a set of switching
application of generator set power to
transistors.
The control circuitry,
the load, and then to system shutdown.
transistors,
and transformer form a
Reference is made to control panel
dc-to-ac converter. As the transistors
assembly controls
and indicators to
alternately turn on and off, they cause
show their relationship to the func-
current to flow in the windings of the
tions they control or display. A
transformer.
When current flows in the
10-1
