Woodward 9907-026, Руководство по эксплуатации продукта

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Load Sharing Module (Analog Output) Manual 02029
10 Woodward
27. Disconnect the wire from terminal 9 that comes from the Phase C CT and
connect both wires from this CT to Terminal 8.
28. Start the generator set and apply full load.
29. Measure the load signal at terminals 22 and 23. If the phase A and B current
transformers are connected correctly, this voltage will be 1/3 lower than the
voltage recorded in step 13. For example; if the reading was 6 volts in step
13, the reading in this step should be 4 volts.
30. Shut down the generator set.
31. Reconnect the Phase C CT wire to terminal 9.
32. If the reading in step 29 was correct, the phasing is correct and there is no
need to perform the Phase Correction Procedure. If the reading in step 29
was not correct, proceed to the Phase Correction Procedure.
Phase Correction Procedure
If this procedure is followed, the correct connection of the current transformers is
assured; the correct CT will be connected to the correct input on the Load
Sharing Module with the correct polarity. Use this procedure only if the Phasing
Check above indicates that the phasing is incorrect.
A CT for any phase (A, B, or C), will produce the most positive load signal
voltage when it is connected, in the proper polarity, to the terminals on the Load
Sharing Module which correspond to the same phase. Any other connections of
this CT will produce a less positive load signal voltage. This procedure makes
trial connections of the first CT to all three CT inputs on the Load Sharing
Module, polarized both ways on each CT input. The load signal voltage is
recorded for each connection, and the CT is then connected to the CT input
terminals that produced the most positive load signal voltage, and with the
polarity that produced the most positive load signal voltage.
In a like manner, the second CT is tried on each of the two remaining CT input
terminals in each polarity, then connected, in the correct polarity, to the terminals
which produced the most positive load signal voltage.
The single remaining CT is then connected to the remaining CT input and the
load signal checked for each polarity. This CT is then connected to the CT input,
polarized so that it produces the most positive load signal voltage.
When the procedure is completed, all three CTs are connected to the proper CT
inputs on the Load Sharing Module, with the correct polarity, and are now labeled
with their correct designations.
The procedure for correcting phase wiring requires that the generator set be shut
down and the current transformers disconnected many times. For convenience
during the phasing check, the temporary method of connecting the current
transformers shown in Figure 3-1 is recommended. By connecting a burden
resistor (a 0.5

, 20 W resistor), across each current transformer, that current
transformer can be disconnected from the Load Sharing Module after removing
all load. The connections between the terminal strip and the Load Sharing
Module can be changed with the generator set running; however, remove all load
before any changes in connections are made. Do not disconnect a wire from a
current transformer with load on the system. After the phase correction
procedure has been completed, remove the terminal strip and the resistors.