TM 9-6115-669-13&P
1.13.6 Electric Power Plant III Functions.
The EPP III (figure 1-6) consists of two identical generator sets 1 and 2. The operation of the
Generator Set 150 kW is described in more detail in manual TM 9-6115-668-13.
Each Generator Set 150 kW has a connection panel with receptacles for the following outputs:
Receptacles L1, L2, L3
3x208 V, 400 Hz output
Receptacle N
Neutral conductor
Receptacle J1
1x120 V, 400 Hz receptacle output (not used for EPP III)
Receptacle J2
24 VDC receptacle output (not used for EPP III)
Receptacle J9
Control connection between generator sets 1 and 2 and power distribution
unit, for parallel operation
Generator set 150 kW output voltages L1, L2, L3, and N pass through individual cables to the PDU
bus bars. From the bus bars, power is distributed among power contactors K3 to K6 for the loads.
Monitoring circuits for overload cutout functions are incorporated into each phase conductor of
these main power circuits.
Overload data is evaluated, together with the sychronization circuit, in the PDU electronics group
N6. If an overload occurs, the phase in question is shut down with power contactor K3, K4, K5, or
K6.
The synchronization system switches the commercial power converter power contactor K40 in and
out; i.e. it acts through cables J6 and J20 in the commercial power converter operating mode.
In addition to the power contactors, the PDU comprises a control device with additional auxiliary
relays, time relays, and a control panel from which all operations are controlled.
The PDU receives power from the bus bars through an internal power supply component that is
active once the generator has reached operating speed.
Until the generator reaches operating speed, the PDU is temporarily supplied with +24 VDC from
the generator by one each of the conductors of cable J9. This supply immediately becomes effective
again if the PDU internal power supply fails.
The EPP III PDU has a connection panel for all connections involved in operating the loads.
Receptacles J1 to J4
Output 3x208 V, 400 Hz (J1 to J3 for RS, J4 for ECS)
Receptacle J5
Control and signal lines between ECS and EPP III
Receptacle J6
R (L1) and S (L2) phases of converter to synchronizing system, where R
(L1) and S (L2) phases of generator are evaluated for voltage and frequency
synchronization
Receptacle J7
Connection for communication line between EPP III and ECS via two
conductors of cable J5
Receptacle J11
1x120 V, 400 Hz receptacle output
Receptacle J12
24 VDC receptacle output
Receptacle J20
Control power contactor K40 in commercial power converter via EPP III
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