Westinghouse WHXC3750, Instruction Manual

 27

OPERATION

12 Volt BattErY CHarging

There are two methods by which the generator can be 

used to charge an external 12 Volt battery:

A.  By direct connection to the generator’s 12-Volt DC 

electrical outlet; or

B.  By using a mains-powered 12 Volt battery charger 

connected to one of the generator’s 240-Volt AC 

outlets

.

Never use either of these methods to charge the 

generator’s own 12 Volt battery.

!

 DANGER

Wet cell batteries produce explosive 

hydrogen gas while charging. If ignited, 

the hydrogen gas mixture can explode 

the battery and cause serious injury 

or blindness. Only charge a battery in 

a well-ventilated area away from any 

sources of ignition such as sparks, 

open flames, matches, cigarettes, Cb 

radios and mobile phones. 
The electrolyte fluid inside a battery 

contains highly corrosive sulphuric 

acid, which upon contact with the 

skin or eyes can cause severe burns 

or blindness. Always wear protective 

glasses and clothing – including  

gloves – when working on a battery. 

Any electrolyte spill should be 

thoroughly flushed clean with water.

battery Charging by Direct Connection

This method is NOT RECOMMENDED and should 

only be used in an emergency. The generator’s 12-

Volt DC electrical output is unregulated and may 

damage the battery due to overcharging.

Tools required (not included) – 12 V DC, 10 A 

minimum battery charging cable with cigarette lighter 

plug for connection to the generator and alligator clips 

(both positive and negative) for connection to the 

battery.

1.  Prepare the battery for charging if it is a user-

maintainable type by removing the vent caps 

and adding demineralized or distilled water until 

the electrolyte level is just above the internal 

battery plates. This may not be possible with a 

maintenance-free battery.

2.  Connect the positive (+) alligator clip (red) to the 

positive (+) terminal on the battery.

3.  Connect the negative (-) alligator clip (black) to the 

negative (-) terminal on the battery.

4.  Start the generator.

5.  Insert the cigarette lighter plug into the generator’s 

12-Volt DC accessory socket. The battery is now 

charging. Keep the battery as far away as possible 

from the generator due to the explosive gas 

hazard.

6.  Monitor the generator’s 12-Volt DC circuit breaker. 

If it switches itself off due to overload as indicated 

by the push button extending out from the control 

panel, reset it manually by pushing it back in. If it 

continues to switch itself off, the current demand is 

too high and the battery cannot be charged by this 

method.

7.  Monitor the battery; stop charging if the battery 

gets hot to the touch and the electrolyte boils 

violently. 

8.  Variables such as battery size and initial state 

of charge make it impossible to definitively 

recommend the charging period. Some batteries 

have a state of charge indicator that can be 

visually checked. Otherwise a voltmeter or 

hydrometer is necessary to accurately determine 

the battery’s condition. A fully charged battery will 

have an open circuit voltage of at least 12.6 V and 

an electrolyte specific gravity of at least 1.265. In 

the absence of any state of charge tools, stop the 

charging after, say, 3 hours and check whether 

the battery is capable of powering the required 

application, e.g. to start a car’s engine. 

9.  Remove the cigarette lighter plug from the 

generator’s 12-Volt DC accessory socket.

10.  Stop the generator unless it’s being used to power 

some other 240-Volt AC device(s).

11.  Disconnect the negative (-) alligator clip (black) 

from the negative (-) terminal on the battery.

12.  Disconnect the positive (+) alligator clip (red) from 

the positive (+) terminal on the battery.

13.  Re-fit the battery’s vent caps, if applicable. The 

battery can now be used.

battery Charging by a Mains-Powered 

Charger

This method is RECOMMENDED. Using a proper 

mains-powered 12 Volt battery charger will ensure that 

the battery is optimally charged and without risk of 

damage due to overcharging.

Tools required (not included) – 240-Volt AC 

powered 12 V DC battery charger.

1.  Prepare the battery for charging if it is a user-

maintainable type by removing the vent caps 

and adding demineralized or distilled water until 

the electrolyte level is just above the internal 

battery plates. This may not be possible with a 

maintenance-free battery.