Woodward 2301E-ST, Installation And Operation Manual

Page: 93 / 126

Manual 26694 2301E-ST
Woodward 91
Figure 5-1. Temporary Wiring for Transformer Phase Correction
1. Shut down the prime mover.
HIGH VOLTAGE—The current transformers can develop dangerously
high voltages. Do not disconnect a current transformer while the
prime mover is running unless temporary 0.5
Ω , 20 W resistors are
installed as shown in Figure 5-1 and all load is removed.
2. Label each CT wire with the phase and polarity that you think it should be. Even though this
identification may prove to be incorrect, this step is necessary so that the individual wires can be
identified during the description of the procedure.
3. Disconnect the phase B CT wires from terminals 6 and 7. Connect these two wires together using a
small screw and nut and tape the connection.
4. Disconnect the phase C CT wires from terminals 8 and 9. Connect and tape these two wires
together as in Step 3.
5. Connect the two wires from the phase A CT to the phase A input terminals 4 and 5.
6. Start the prime mover, apply full load and monitor the load sensor output. Start a list and record this
value.
7. Unload the system and reverse the phase A CT wires on terminals 4 and 5.*
8. Apply full load, monitor the load sensor and record this value.
9. Unload the system, remove phase A CT wires from terminals 4 and 5 and connect them to phase B
input terminals 6 and 7.*
10. Apply full load, monitor the load sensor and record this value.
11. Unload the system and reverse the phase A CT wires on terminals 6 and 7.*
12. Apply full load, monitor the load signal and record this value.
13. Unload the system, remove phase A CT wires from terminals 6 and 7 and connect them to phase C
input terminals 8 and 9.*
14. Apply full load, monitor the load sensor and record this value.
15. Unload the system and reverse the phase A CT wires on terminals 8 and 9.*
16. Apply full load, measure the load signal and record this reading.
17. Unload the system and compare the six readings taken.*
18. Remove the phase A CT wires from terminal 8 and 9 and connect the phase A wires to the pair of
terminals that produced the highest positive load value and in the polarity that produced the highest
positive load value.
19. Remove tape and disconnect the phase B CT wires. Connect the phase B CT wires to one pair of
the two remaining pairs of CT input terminals on the load sensor.
20. Apply full load and measure the load signal. Start a new list and record this reading.
21. Unload the system and reverse the phase B CT wires on the same terminals.*
22. Apply full load, measure the load signal and record this reading.
23. Unload the system, remove phase B CT wires and connect them to the other pair of terminals.*
24. Apply full load, measure the load signal and record this reading.
Released