Guardian Technologies 4389, 4456 Test 30 Check Fuses F1 and F2, Test 31 Test Limit Switch XA1

V-TYPE PREPACKAGED TRANSFER SWITCHES

PART 3

SECTION 3.4

DIAGNOSTIC TESTS

6.Set the generator main line circuit breaker to its "On" or "Closed" position.

7.Set the generator AUTO-OFF-MANUAL switch to AUTO.

a.The generator should crank and start.

b.About 15 seconds after engine startup, the transfer relay should energize and transfer to the ’Standby" source should occur.

8.When you are certain that transfer to "Standby" has occurred, turn ON the utility power supply to the transfer switch. After a 15 seconds, retransfer back to the "Utility" source should occur.

9.Locate on the utility closing coil the terminal that Wire A is connected to (see Figure 1, Page 3.4-1). Connect the

other meter test lead to this terminal. Generator line to line voltage should be indicated. If generator voltage is NOT indicated, proceed to Step 10.

10.With Wire N2A still connected to one test probe, connect the other meter test lead to Wire 126 on Limit Switch XA1 (see Figure 1, Page 3.4-1). Generator line to line voltage should be measured.

RESULTS:

1.In Step 7, if the generator does NOT crank or start, refer to Part 4, "DC Control".

2.In Step 7, if transfer to the "Standby" source does NOT occur, go to Problem 1.

3.In Step 9, if normal utility source line-to-line voltage is indicated but retransfer back to "Utility" does NOT occur, go to Test 24.

4.If normal utility source line-to-line voltage is NOT indicated in Step 9, but is indicated in Step 10, proceed to Test 31.

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.

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