Section 3 — Operation
Guardian
Figure 3.2 – Manual Transfer Switch Operation | 3.6 SETTING THE EXERCISE TIMER |
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.
The generator is equipped with an exercise timer. Once it is set, the generator will start and exercise once every seven days, on the day of the week and at the time of day the following sequence is completed. During this exercise period, the unit runs for approx- imately 12 minutes and then shuts down. Transfer of loads to the generator output does not occur during the exercise cycle.
A switch on the control panel (see Figure 3.1) permits selection of the day and time for system exercise. To select the desired day and time of day, the following sequence must be performed at that time.
1.Verify that the AUTO/OFF/MANUAL switch is set to AUTO.
2.Hold down the set timer switch until the genera- tor starts (approximately 10 seconds) and then release.
3.The generator will start and run for approximately 12 minutes and then shut down on its own. The exerciser will then be set to run at that time of day every week.
NOTE:
The exerciser will only work in the AUTO mode and will not work unless this procedure is per- formed. The exerciser will need to be reset every time the
3.7PROTECTION SYSTEMS
3.7.1 LOW OIL PRESSURE SWITCH
This switch (Figure 3.3) has normally closed contacts that are held open by engine oil pressure during crank- ing and operating. Should oil pressure drop below the 8 psi range, switch contacts close, and the engine shuts down. The unit should not be restarted until oil is added, and the AUTO/OFF/MANUAL switch must be turned to OFF and then back to AUTO.
3.7.2 HIGH TEMPERATURE SWITCH
This switch’s contacts (Figure 3.3) close if the tem- perature should exceed approximately 140º C (284º F), initiating an engine shutdown. The generator will automatically restart and the LED will reset once the temperature has returned to a safe operating level.
16 Generac® Power Systems, Inc.