Electric Generator Battery: 6 Important Answers for Beginners

Electric generators have batteries! This may be insane for non electrical workers. However, I have found some important questions about generator batteries, I will answer these questions to help you. Let’s get started.

Why does an electrical generator need a battery?

Batteries are an integral component of the generator‘s set. The primary function of an electrical generator battery is to provide the starting motor of the generator with energy when a power interruption occurs.

Batteries may also be able to provide:

  • Power supply to electronic control system of the generator.
  • Almost all electrical components of the generator need DC power, like solenoids, sensors and control panel. Even the fuel solenoid works on DC, with out batteries it won’t operate.
  • During generator operations, batteries may supply electricity to the other DC components and lighting inside the generator enclosure.

The battery plays a vital role in sensing when the engine is off to feed the starter motor. Electronic components need to be operated as well; it’s just like the car battery; it plays a role in generator operation. The engine starts with the battery since it would not begin without it.

Most generator sets utilize the standard lead-acid battery. There are two kinds of batteries:

How Does a Generator Charge its Own Battery?

Generator charges its own battery Using the power of its engine.

The charging system, which charges generator batteries, is a simple Dynamo (DC generator, like the one in you car), it’s directly connected to the batteries.

It charges the batteries when the generator is working. If the generator is stand by, out of service, we use a separate charging power supply to keep the batteries charged.

Why my generator not charging the battery?

If the generator is not charging the battery, some possible reasons are mentioned below:

Battery Itself Is the Problem

If a generator fails to recharge the battery, we accuse the generator. But the generator isn’t always the cause. The factors that could stop batteries from being charged are:

Batteries have a short lifespan. They’re not built to last forever. So, if the battery you have is old or in the case of a defective cell, you can’t believe it will keep its charge for an extended duration.

Also, think about the possibility that your generator could charge the battery. However, the battery may not maintain the charge. Instead, it continues to charge at a constant rate even when the generator operates.

The generator is In Storage for A Long-time

If the generator is put in storage for an extended time, the battery can discharge at that end; it cannot be recharged furthermore.

In the absence of a regular charge, you’ll decrease the battery’s capacity and lifespan and reduce its capacity to maintain its charge.

You should follow the generator manufacturer instructions about how to keep your battery healthy during long periods storage.

Faulty Charger

The generator charger could stop it from charging your battery. Unfortunately, charger problems are not easy to identify because they may appear from various angles.

Generators have cables running between the battery and the generator, that become faulty sometimes; you must check the cables and make sure they are connected.

Tripped Breakers & Fuses

Be sure to inspect the fuses and breakers. Tripped breakers could affect the generator’s capability to charge the battery.

Battery charging circuit is protected by fuses or circuit breakers, or both, in case of any fault these protection devices should do what it is designed to do, trip the circuit.

You should check for the reason that caused the circuit breaker to trip and fix it before you close the CB or change the fuse.

How to fix the Generator Battery Not Charging

To fix this “Generator not charging” issue, first identify the source of the issue. Then, the most efficient solutions are:

Replace The Fuse

This is the most straightforward problem to solve. If the fuse inside the transfer switch is blown, it is easy to replace it.

If you’ve worked using electrical tools, the process shouldn’t take too long.

If the fuse does not seem to be the issue, then look at the breakers. A tripped breaker could hinder the generator’s ability to charge the battery fully.

Replace The Battery

It is worth replacing the battery if you own an older generator, mainly if you do not use the generator regularly.

If the battery cannot keep its charge, replace it. There’s no alternative in this instance.

How do you test generator battery?

Here we discussed two types of tests performed separately for Dry Batteries, also called maintenance free batteries and Led-Acid Batteries called electrolyte batteries.

Conductance Test (For Maintenance Free Batteries):

For most conductance testers, you will see the voltage reading and the light green/red, or pass/fail. The typical voltage for a 12-volt battery is 12.6 volts. Consistency is the key to indicating the health of the battery. When conducting conductance tests monthly, it will become apparent that a pattern is emerging.

If you notice a noticeable decrease in voltage during testing every month, the battery is damaged and requires replacement.

The inspectors will be looking for voltage fluctuations or a failure designation in the test report. It is crucial to remember that temperature is integral in conductance readings.

If batteries are located outside, and in the open air, the temperature of the surrounding air when conducting conductance test must be recorded. If your tester displays Cold Cranking Amps, the reading should be in or close to the amperage stated by the manufacturer on the device.

If your tester shows a green/red or pass/fail rather than actual amps, note the results in your test record.

Hydrometer Testing (For Electrolytes Batteries):

Utilize a hydrometer to determine the exact gravity and level in charge for the sulphuric acid within the battery using following Method:

  • Do not add to the water that has been distilled.
  • Maintain the barrel is standing up. Inject enough electrolyte into each cell so that the float can glide around without issue.

Then, you should read off the hydrometer from eye level.

  • 1.270 to 1.280 SG Full Charge.
  • 1.220 to 1.230 SG Half Charge.
  • 1.150 to 1.220 SG Discharged.

The readings from each cell should remain within 0.030 points. If the deviation is more significant than 0.030, your battery probably requires replacement.

If all cells are consistently low, the battery could likely be able to be repaired, but we suggest replacing the battery immediately if it is feasible. All Battery maintenance is best done by a certified technician familiar with batteries.

Can you jump start a generator battery?

Yes, we can jump start a generator battery. To get a generator jump start, you only need to correctly connect an external power source, DC, to the generator and then generate the power.

Although the job may seem effortless and secure, you cannot be 100% certain of these aspects, which is why it is imperative to carry a safety kit at all times.

You should not connect the batteries the wrong way, double check polarities before connection.

What Happens to a Battery if Short Circuit Its Terminals?

If you short circuit a battery, It will overheat, leak, and potentially explode.

If the battery can generate a high current, it can induce overheating of the wire or other object shorting the terminals, posing a burn/fire hazard.

When you externally short-circuit a battery, internal resistance restricts the current. The short circuit current will be little, still dangerous, if the internal resistance is high.

The internal resistance of older, non-rechargeable batteries is often high. The internal resistance of the carbon-zinc battery you linked to is likely to be high.

Internal resistance is meager in compact lead, NiMH, and lithium-ion/polymer batteries. If you short one out, you can get a huge spark and a lot of heat. So, don’t short any of these batteries!

A short circuit is a short circuit, no matter the kind of power source AC or DC. The same thermal and mechanical effect can cause serious damages and human injuries.

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