Section Ill. PRINCIPLES OF OPERATION

TM 9-6115-661-13&P

Section Ill. PRINCIPLES OF OPERATION

1-13 FUNCTIONAL DESCRIPTION.

1-13.1 Power Unit Functional Description. The Power Units are mobile power sources and each

consists of a Tactical Quiet 15 kW Generator Set mounted on a modified trailer. The generator set

consists of a liquid-cooled diesel engine, brushless generator, excitation system, speed governing system,

fuel system, 24-volt direct current starting system, control system, and malfunction protection system.

The generator set has a reconnection board that has been initially positioned to allow a power output of

either 120/208-volt, three phase or 240/416-volt, three phase AC power. The PU-801, PU-801A and

PU-802 use a DOD Model MEP-804A Generator Set operating at 60 Hz with a load capacity of 15 kW.

The PU-800 uses a DOD Model MEP-814A Generator Set operating at 400 Hz. System or equipment load

cables are to be connected to the load terminals on the generator set output panel. Refer to

TM 9-6115-643-24 for functional description of the generator set. The PU-800 and PU-802 are mounted on

a 2 1/2 ton trailers. The PU 801 is mounted on a 1 ton trailer and referred to as the lightweight 15 kW

generator set. The PU-801A is mounted on a high mobility trailer. Refer to TM 9-2330-205-14&P for

functional description of the 2 1/2 ton trailer, TM 9-2330-202-14&P for the functional description of the 1

ton trailer, and TM 9-2330-392-14&P for the functional description of the high mobility trailer.

1-13.2 Power Plant Functional Descriptions. The Power Plant consists of two PU-800 Power Units, a

switch box and power cable. The two PU-800 Power Units have been modified to provide independent

switching between the Power Units. One PU-800 is modified by moving the accessory storage box to the

curbside fender, adding a switch box and identifying the modified PU-800 as AN/MJQ-39 unit A. The

other PU-800 is modified by adding a power cable and identifying the modified PU-800 as AN/MJQ-39

unit B. Refer to paragraph 1-13.1 for the functional description of the PU-800. Output electrical power is

normally supplied through the switch box assembly located on unit A. The cable supplied with unit B

connects the generator sets through the switch box on unit A. The control panel of the switch box controls

the output source. The output source is usually either the unit A or unit B generator set as determined by

the control panel switches. When both switches are placed in the ON position and both generators are

on, the generators operate in parallel. The parallel operation of the generators allows for an

uninterrupted load transfer between unit A and unit B. The output power cable to external equipment

may be connected to the switch box from either connector J1 or load terminals (L0, L1, L2, L3, and GND)

of the switch box. When connection is required from the generators, parallel operation is not lost. Refer

to TM 9-6115-643-10 for operation and TM 9-6115-643-24 for a detailed functional description of the

generator sets without a switch box.

1-14 RELATED TECHNICAL MANUALS.

Refer to Appendix A for related technical manuals.

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