User manual

56 Maintenance
UM6C28C P0728920 Standard 11.00 April 2001 Emerson Energy Systems
WARNING
Precautions to take to avoid service interruptions
When working on a live power system, the low voltage
disconnect contactor (if provided) should be kept from
tripping. To do this, insert a 1/4-inch ( 3 mm ) wide
electrically isolated tool ( preferably plastic ) in the small
opening on the side of the contactor assembly to lock it
closed. See Figure 19.
Procedure 2 – Replacing the NT6C14PG meter display card
Step Action
1 Open the front door of the control and distribution panel.
2 If the system is provided with an LVD feature, insert a 1/4-inch ( 3
mm ) wide electrically isolated tool in Figure 19.
3 Disconnect and insulate the ends of the brown, yellow, black and red
wires connected to terminals E1, E2, E3 and E4 on the meter display
card.
4 Remove the nut that secures the VOLT/AMPS switch to the font
door.
5 Remove the four mounting screws securing the meter display card in
place, then remove the card.
6 Install the new meter display card and secure it in place by installing
the four mounting screws.
7 Secure the VOLT/AMPS switch to the font door with the appropriate
nut.
8 If the new card is not provided with wires on terminals E1, E2, E3
and E4, connect the wires disconnected in step 4 directly to the E1,
E2, E3 and E4 terminals.
If the new card is provided with wires on terminals E1, E2, E3 and
E4, cut these wires approximately 2” long, then splice them to the
wires disconnected instep 4, matching the colors.
9 Set the switches of the S3 DIP switch module as follows: 1 and 4 in
the ON position, 2, 3, 5 and 6 in the OFF position ( see Figure 20 ).
10 If the system is provided with an LVD feature, remove the electrically
isolated tool installed in step 2.
11 Calibration
Putthe VOLT/AMPS switch on the front door in the AMPS position.
12 Connect an external digital multimeter set for a 2 V dc reading
across system shunt E1 and E2 terminals on the meter display card.
13 Verify that the reading in amperes on the meter display of the control
and distribution panel is equal to five times the reading in millivolts
on the external digital multimeter.
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