Bryant ASPAS1BBA015 - Manual (Page 67)

Page 67
SECTION 3.4
DIAGNOSTIC TESTS
5. If normal utility source line-to-line voltage is NOT
indicated in Step 8, and is NOT indicated in Step 9,
proceed to Test 32.
TEST 30 - CHECK FUSES F1 AND F2
DISCUSSION:
Fuses F1 and F2 are connected in series with the
Utility 1 and Utility 2 circuits, respectively. A blown
fuse will open the applicable circuit and will result in
(a) generator startup and transfer to "Standby", or (b)
failure to retransfer back to the utility source.
Figure 5. Fuse Holder and Fuses
PROCEDURE:
1. On the generator panel, set the Auto-Off-Manual switch
to OFF.
2. Turn off the utility power supply to the transfer switch,
using whatever means provided.
3. Remove fuses F1 and F2 from the fuse holder (see
Figure 5).
4. Inspect and test fuses for blown condition.
RESULTS:
1. Replace blown fuse(s) and proceed to Test 34.
2. For Problem 7 (DC Control section), go to Test 27.
TEST 31 - TEST LIMIT SWITCH XA1
DISCUSSION:
When the transfer switch main contacts are actuated
to their "Utility" position, limit switch XA1 should be
mechanically actuated to its open position. On
transfer to the "Standby" position, the limit switch
should actuate to its closed position. If the switch
does not actuate to its closed position, retransfer back
to "Utility" will not occur.
PROCEDURE:
1. With the standby generator shut down, set its Auto-Off-
Manual switch to OFF.
2. Turn OFF the utility power supply to the transfer switch,
using whatever means provided.
3. To prevent interaction, disconnect Wire 126 and Wire "A"
from the limit switch terminals.
4. Set a VOM to its "R x 1 " scale and zero the meter.
5. Connect the VOM test leads across the two limit switch
terminals from which Wires A and 126 were removed.
6. Manually actuate the main contacts to their "Standby"
position. The VOM should indicate CONTINUITY.
7. Manually actuate the main contacts to their "Utility"
position. The VOM should read infinity.
RESULTS:
Replace limit switch XA1 if it checks bad.
NOTE: Problems with transfer switch operation
can also be caused by (a) defective wiring
between the generator and transfer switch, or (b)
a defective component in the generator circuit
board. See Part 4, "DC Control".
TEST 32 - CONTINUITY TEST OF WIRING (C1)
DISCUSSION:
This test will ensure that all control wiring has
continuity.
1. Set the Auto-Off-Manual switch to the OFF position.
2. Turn the generator main circuit breaker to the off
position.
3. Turn off the utility power supply to the transfer switch
using whatever means provided. (Such as utility source
main line circuit breaker).
4. Set your VOM to the "R x 1" scale.
5. Disconnect Wire N2A from the Utility Coil C1 and
connect one test lead to it. Connect the other test lead
to terminal lug N2 of the transfer switch. CONTINUITY
should be read. Reconnect Wire N2A.
6. Disconnect Wire 126 from transfer relay (TR) and
connect one test lead to it. Connect the other test lead
to limit switch XA1 bottom terminal Wire 126.
CONTINUITY should be read. Reconnect Wire 126.
“V-TYPE” PREPACKAGED
TRANSFER SWITCHES
PART 3