TM 9-6115-669-13&P
2.7.5 Operating Mode Changeover.
An operating mode changeover may be made for the following reasons:
1. Parallel operation
‘lb distribute generator power, e.g. for cooling purposes.
2. Changeover
Changeover to alternate generator due to malfunction or maintenance
requirement. Changeover due to change in configuration, e.g.
shutdown of external power input from commercial power converter.
3. Temporary/emergency
Battle Short or idle operation; Emergency Shutdown.
changeovers
2.7.5.1 Parallel Operation of Generator Sets.
Initial status: Generator set 1 in operating mode.
a.
Start up second generator set as instructed in paragraph 2.7.2.1. Allow the second generator
set to idle.
b. Press PARALLEL OPERATION ON illuminated pushbutton switch (10, figure 2-22) on
generator set. The PARALLEL OPERATION ON lamp (10) lights up. After synchronization,
the second generator set is automatically switched on line and the PARALLEL OPERATION
ON lamp (10) then goes out.
Both generator sets are now on line with a power distribution of approximately 60%. If one
generator set fails, the remaining generator set will, without interruption, supply full power output
to the loads.
2.7.5.2 Switching Between Generator Sets.
Initial status: Parallel operation of generator sets 1 and 2.
Press AC CIRCUIT INTERRUPTER OFF pushbutton switch (9, figure 2-22) on generator set
(1 or 2). The generator set (1 or 2) will switch to idle and can then be shut down (paragraph
2.8.1).
2.7.5.3 Switching from EPP III to Commercial Power Converter.
Initial status: Generator set 1 or generator set 2 or both are supplying power.
Commercial power converter runs idle.
a.
Set frequency and voltage on EPP III generator:
Use control elements (4, 7, figure 2-22) to set frequency to 400.0 +/- 0.2 Hz
Use control elements (1, 2, 3) to set voltage to 208 +/- 2 V
b. Press PARALLEL OPERATION ON illuminated pushbutton switch (13) on PDU control panel.
The PARALLEL OPERATION ON lamp (13) lights up. Once changeover is complete
PARALLEL OPERATION lamp (11) lights up, and PARALLEL OPERATION ON lamp (13)
goes out.
The commercial power converter is now providing power.
2.7.5.4 Switching from Commercial Power Converter to EPP III.
Initial status: Commercial power converter is supplying power; EPP III generator is shut down (or
idling).
a.
Start up generator set as instructed in paragraph 2.7.2.1. Allow the generator set to idle.
b.
Press PARALLEL OPERATION ON illuminated pushbutton switch (13, figure 2-22).
The PARALLEL OPERATION ON lamp (13) lights up. Once changeover is complete
PARALLEL OPERATION lamp (11) lights up, and PARALLEL OPERATION ON lamp (13)
goes out. The EPP III generator is now providing power.
2.7.5.5 Switching ECS/RS Loads to the Commercial Power Converter.
Initial status: Commercial power converter is supplying power; EPP III generator is shut down.
Set ECS ON switch (16, figure 2-22) and RS ON switch (14) to on.
2.7.5.6 Emergency shutdown.
NOTE
The Emergency Shutdown function will not operate when the Battle
Short function is active, since the latter function has a higher priority.
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