Generac Power Systems 55, 75, 65 Amp Fuse, Fuel Primer Switch, Start-Stopswitch, 5.– Primer Switch

Section 5

ENGINE DC CONTROL SYSTEM

The following chart applies:

CABLE LENGTH (IN FEET)	RECOMMENDED CABLE SIZE
0-10	No. 2
11-15	No. 0
16-20	No. 000

EFFECTS OF TEMPERATURE:

Battery efficiency is greatly reduced by a decreased electrolyte temperature. Such low temperatures have a decided numbing effect on the electrochemical action. Under high discharge rates (such as crank- ing), battery voltage will drop to much lower values in cold temperatures than in warmer temperatures. The freezing point of battery electrolyte fluid is affected by the state of charge of the electrolyte as indicated below:

SPECIFIC GRAVITY	FREEZING POINT
1.220	-35° F. (-37° C.)
1.200	--20° F. (-29° C.)
1.160	0° F. (-18° C.)

ADDING WATER:

Water is lost from a battery as a result of charging and discharging and must be replaced. If the water is not replaced and the plates become exposed, they may become permanently sulfated. In addition, the plates cannot take full part in the battery action unless they are completely immersed in electrolyte. Add only DISTILLED WATER to the battery. DO NOT USE TAP WATER.

NOTE: Water cannot be added to some “mainte- nance-free” batteries.

CHECKING BATTERY STATE OF CHARGE:

Use an automotive type battery hydrometer to test the battery state of charge. Follow the hydrometer manu- facturer's instructions carefully. Generally, a battery may be considered fully charged when the specific gravity of its electrolyte is 1.260. If the hydrometer used does not have a “Percentage of Charge” scale, compare the readings obtained with the following:

SPECIFIC GRAVITY	PERCENTAGE OF CHARGE
1.260	100%
1.230	75%
1.200	50%
1.170	25%

CHARGING A BATTERY:

Use an automotive type battery charger to recharge a battery. Battery fluid is an extremely corrosive, sulfu- ric acid solution that can cause severe burns. For that reason, the following precautions must be observed:

❏The area in which the battery is being charged must be well ventilated. When charging a battery, an explosive gas mixture forms in each cell.

❏Do not smoke or break a live circuit near the top of the battery. Sparking could cause an explosion.

❏Avoid spillage of battery fluid. If spillage occurs, flush the affected area with clear water immediately.

❏Wear eye protection when handling a battery.

7.5 AMP FUSE
This panel-mounted Fuse
protects the DC control
circuit against overload
and possible damage. If
the Fuse has melted open
due to an overload, nei-
ther the priming function
nor the cranking function
will be available.	Figure5-4

FUEL PRIMER SWITCH

Following generator installation and after the unit has been idle for some time, the fuel supply line may be empty. This condition will require a long cranking peri- od before fuel can reach the carburetor. The Fuel Primer Switch, when actuated to its “PRIME” position will deliver battery voltage across the closed switch contacts to the Fuel Pump (FP) to turn the Pump on. Pump action will then draw fuel from the supply tank to prime the fuel lines and carburetor.

Figure 5-5. – Primer Switch

START-STOP SWITCH

The Start-Stop Switch allows the operator to control cranking, startup and shutdown. The following wires connect to the Start-Stop Switch:

1.Wire No. 17 from the Engine Controller circuit board. This Is the CRANK and START circuit. When the Switch is set to 'START”, Wire 17 is connected to frame ground via Wire OB.

a.With wire 17 grounded, a Crank Relay on the circuit board energizes and battery volt-

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