Section 3 — Operation
Guardian
D.Utility Voltage Pickup Sensor | Figure 3.2 – Manual Transfer Switch Operation |
• This sensor monitors utility power supply volt- |
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age. When that voltage is restored to above 70 |
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percent of the nominal source voltage, a retrans- |
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fer time delay starts timing. |
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E.Retransfer Time Delay |
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• This timer runs for about 15 seconds. |
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• At end of a |
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switch. |
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• Retransfer to utility power source then occurs. |
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F. Engine |
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• When the load is transferred back to utility power |
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source, the engine |
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• The timer will run for about one minute, and the |
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generator will then shut down. |
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3.5MANUAL TRANSFER OPERATION
3.5.1 TRANSFER TO GENERATOR POWER SOURCE
To start the generator and activate the transfer switch manually, proceed as follows:
1.Set the generator’s main circuit breaker to its OFF (or open) position.
2.Set the generator’s AUTO/OFF/MANUAL switch to OFF.
3.Turn OFF the utility power supply to the transfer switch using the means provided (such as a utility main line circuit breaker).
DANGER
Do not attempt to activate the transfer switch manually until all power voltage supplies to the switch have been positively turned off. Failure to turn off all power voltage supplies may result in extremely hazardous and possibly fatal electrical shock.
4.Use the manual transfer handle inside the trans- fer switch to move the main contacts to their “Standby” position, i.e., loads connected to the standby power source (Figure 3.2).
5.To crank and start the engine, set the AUTO/OFF/ MANUAL switch to MANUAL.
6.Let the engine stabilize and warm up for a few minutes.
7.Set the generator’s main circuit breaker to its ON (or closed) position. The standby power source now powers the loads.
3.5.2 TRANSFER BACK TO UTILITY POWER SOURCE
When utility power has been restored, transfer back to that source and shut down the generator. This can be accomplished as follows:
1.Set the generator’s main circuit breaker to its OFF (or open) position.
2.Let the engine run for a minute or two at
3.Set the generator’s AUTO/OFF/MANUAL switch to its OFF (or open) position. The engine should shut down.
4.Check that utility power supply to the transfer switch is turned OFF.
DANGER
Do not attempt to activate the transfer switch manually until all power voltage supplies
to the switch have been positively turned off. Failure to turn off all power voltage supplies may result in extremely hazardous and possibly fatal electrical shock.
5.Use the manual transfer handle inside the trans- fer switch to move the main contacts back to their “Utility” position, i.e., loads connected to the util- ity power source (Figure 3.2).
6.Turn ON the utility power supply to the transfer switch using the means provided.
7.Set the system to automatic operation as outlined in “Automatic Transfer Operation,” Section 3.3.
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