3.2USING THE AUTO/OFF/MANUAL SWITCH (FIGURE 3.1)

Section 3 — Operation

Guardian Air-cooled 7 kW, 12 kW and 15 kW Generators

11.Drain the oil and remove the oil filter. Replace the oil filter according to Section 4.4, “Changing the Oil Filter” (Page 18). Replace the oil with synthet- ic oil as recommended in Section 4.3, “Changing the Engine Oil” (Page 17).

12.Reconnect the battery cables as outlined in “General Hazards” (page 2) and insert the 5A and 15A fuses into the generator control panel. The generator is now ready for service.

3.2USING THE AUTO/OFF/MANUAL SWITCH (FIGURE 3.1)

‹3.2.1 “AUTO” POSITION

Selecting this switch position activates fully automat- ic system operation. It also allows you to start and exercise the engine every seven days with the setting of the exercise timer (see Section 3.6, Page 16). This position also is used for remote starting, when it is set up.

‹3.2.2 “OFF” POSITION

3.3AUTOMATIC TRANSFER

OPERATION

To select automatic operation, do the following:

1.Make sure the transfer switch main contacts are set to their “Utility” position, i.e., loads connected to the utility power source (Figure 3.2, Page 15).

2.Be sure that normal utility power source voltage is available to transfer switch terminal lugs N1 and N2.

3.Set the generator’s Auto/Off/Manual switch to AUTO.

4.Set the generator’s main circuit breaker to its ON (or closed) position.

With the preceding steps complete, the generator will start automatically when utility source voltage drops below a preset level. After the unit starts, loads are transferred to the standby power source. Refer to Section 3.4, “Sequence of Automatic Operation.”

3.4SEQUENCE OF AUTOMATIC OPERATION

This switch position shuts down the engine. This position also prevents automatic operation.

‹3.2.3 “MANUAL” POSITION

Set the switch to Manual to crank and start the engine. Transfer to standby power will not occur unless there is a utility failure.

Figure 3.1 – Generator Control Panel

The generator’s control panel houses a control logic circuit board. This board constantly monitors utility power source voltage. Should that voltage drop below a preset level, circuit board action will signal the engine to crank and start. After the engine starts, the circuit board signals the transfer switch to activate and connect load circuits to the standby power sup- ply (load terminal lugs T1/T2 connect to terminal lugs E1/E2).

FUSE

 

5A

OFF MAN.

AUTO

FUSE

 

15A

SET

 

EXERCISE

 

TIME

L o c a t e y o u r n e a r e s t ‹3.2.1 “AUTO” POSITION‹3.2.2 “OFF” POSITION3.3AUTOMATIC TRANSFER d e a le r a t :

3.4SEQUENCE OF AUTOMATIC OPERATIONPOWER SYSTEMS, INC.

SYSTEM SET

LOW OIL

HIGH TEMP.

OVER SPEED

OVER CRANK

F L A S H IN G G R E E N L E D =

N O U T IL IT Y S E N S E 4 F L A S H IN G R E D L E D S =

E X E R C IS E R N O T S E T

Upon restoration of utility source voltage above a pre- set level, generator circuit board action signals the transfer switch to transfer loads back to that power supply. After retransfer, the engine is signalled to shut down.

The actual sequence of operation is controlled by sensors and timers on a control logic circuit board, as follows:

A.Utility Voltage Dropout Sensor

• This sensor monitors utility source voltage.

• If utility source voltage drops below about 70 per-

cent of the nominal supply voltage, the sensor

energizes a 15-second timer.

With the switch set to AUTO, the engine may

!crank and start at any time without warning. Such automatic starting normally occurs when utility power source voltage drops below a pre- set level or during the normal exercise cycle. To prevent possible injury that might be caused by such sudden starts, always set the switch to OFF and remove the fuses before working on or around the generator or transfer switch. Then, place a “Do Not Operate” tag on the gen- erator panel and on the transfer switch.

14 Generac® Power Systems, Inc.

• Once the timer has expired, the engine will crank

and start.

B.Engine Warm-up Time Delay

• This mechanism lets the engine warm up for

about 10 seconds before the load is transferred

to the standby source.

C.Standby Voltage Sensor

• This sensor monitors generator AC output volt-

age. When the voltage has reached 50 percent of

the nominal rated voltage, transfer to standby

can occur.

Page 16
Image 16
Generac 04389-1, 04456-1, 04390-1 owner manual 3.3AUTOMATIC TRANSFER OPERATION, 3.2USING THE AUTO/OFF/MANUAL SWITCH FIGURE