Generator Care Generator Troubleshoot

5 Common Reasons a Generator Not Producing Power (Solution)

Assuming you just took your generator out of storage for a spin only to be surprised it’s not producing power. The engine is starting and running okay, but nothing is coming out of the generator outlets. If that is the case with your generator, you must ask yourself, ‘why is my generator not producing power?’

Well. There is more than one culprit for such a problem. All you need is to troubleshoot it from the most obvious culprit and work your way to the least. Here are the possible causes of your generator not producing power:

  • Tripped or Defective Breaker
  • Loss of Residual Magnetism
  • Worn-out Brushes
  • Defective AVR
  • Defective Capacitor, or
  • Dead alternator

All these issues are easy to fix except the dead alternator. If your generator isn’t producing power, this post will take you through a series of steps to solve the problem. Read along.

How to Troubleshoot Generator Not Producing Power

When dealing with a generator not producing power, it’d be best to troubleshooting the generator from the outlet and work your way to the alternator. Things get complicated as you start to take some part of the generator apart. But I will keep this guide as simple as possible to make sure you can manage the fixing by yourself.

a) Tripped or Faulty Breaker

All generators come with at least one type of breaker for each of their power outlet. They trip or disconnect the electric supply when there is a potential danger to your connected devices.

Circuit Breakers

They help protect the appliances from unexpected surges. For example, they will usually trip when the electric supply is higher than what is needed; it detects overloading.

It will happen every time you try getting more power from the generator than its capacity. An example is when you connect a 1200-watt mini-AC to a 1Kw generator.

The generator will automatically trip the circuit breaker to protect itself and the mini-AC. The same can happen when you use the wrong gauge wire or when you plug in multiple cords once.

When the circuit breakers trip, you won’t get any power. The generator will typically be running, but you will need to reset the breakers to resume the power supply.

GFCI Breakers

All generators come with Circuit Breaker (fuses), but only some come with GFCI Breaker. The GFCI is somewhat different from the circuit breakers but functions the same, cutting the power supply.

GFIC breakers trip when they sense not enough power completing the circuit through the designated route. With electricity tries to find the easiest and shortest way to the ground and takes the path with the least resistance, the GFCI breakers will trip every time it gets an alternate pathway.

An example is when you’re using an extension cord with a small nick to power your home appliances. When the power passes through, the wet grass reroutes the current to earth through water, and the circuit never completes. The GFCI breaker trips and cuts the power supply through the outlet.

The tripping might be caused by a specific item, both the circuit breakers and GFCI breakers; it might be nothing to do with the generator. So it’d be best to test the items individually to be sure which one is tripping the breakers.

Unplug the extension cord and inspect it to make sure it doesn’t have any exposed wires. If damaged, get an extension cord replacement right away. Also, make sure you match the wire gauge with the outlet you’re drawing power from.

If you’re in a true emergency and you’re confident that a specific generator breaker is defective, you can bypass them technically. However, there is a warning.

WARNING: Bypassing the circuit breakers is tempting but also dangerous. I highly advise against it as it can lead to generator and appliance damages, not forgetting possible injury risks.

How to Test a Faulty Breaker

Some generators come with breakers with colored LED beside them to indicate when they are tripped, and some don’t have any.

Try switching the circuit or GFCI breaker on and off and try the generator outlet again. If nothing improves, you will have to test it with a multimeter to measure the resistance of the wire connections from the electrical panel inside.

If the multimeter reads any resistance, the breaker is good. But if the multimeter reads infinity or OL (overload), the breaker is faulty and needs replacing.

How to Replace a Faulty Breaker

  • Remove the generator spark plug to make sure there will be no accidental starting.
  • Unscrew the nuts or screws holding the outlet housing.
  • While noting the wire orientation on the breaker, disconnect the two or three power harnesses and open the outlet housing cover.
  • Using a flat-head screwdriver, press the breaker tabs to release. You can reuse the protective cover from the faulty breaker.
  • Snap-in your new breaker and reconnect the wires as they were.
  • Take back the cover and screws as you found them.

b) Faulty Automatic Voltage Regulator

The automatic voltage regulator (AVR) of a generator regulates and balances voltage output produced by the alternator. And you know what, all generator AVRs come with an adjustment screw for fine-tuning the voltage output.

Troubleshooting a faulty AVR requires you to exploit the process of elimination. First, assuming you’ve tested the breakers, and they are all okay, test the wiring insider the generator electrical panel, those running from the stator to the breaker.

If they are okay, try to adjust the AVR to keep it in line. If no change in the output, there may be a problem with the AVR – dead or not enough power is getting to it. Unfortunately, it’s not easy to know if the AVR is dead unless you have a working model.

But, you can use a multimeter to check the resistance (within the manufacturer’s specifications – generally between 3 and 5 ohms) between the two terminals connecting to the brushes. If higher (OL), then the AVR is faulty and needs a replacement.

How to Replace a Faulty AVR (Automatic Voltage Regulator)

If you’re confident the AVR is faulty, get a replacement. AVRs come in various sizes and shapes. So it’s pretty easy to replace. All you need is to:

  • Unplug your spark plug. Prevents accidental starting
  • Unscrew the alternator cover
  • Disconnect the two spade connectors connecting the AVR to the brush assembly.
  • Disconnect the quick-connector connecting the AVR to the alternator.
  • Unscrew the AVR
  • Connect the new AVR replacement and reverse the steps

c) Worn-out Carbon Brushes

If the generator produces no power after connecting the new AVR, the problem might be more profound in the alternator. So the next step is to check the generator carbon brushes to ensure they are working right – ensure they are making the right contact with the rotor.

You have to disconnect the AVR (looks like a car brake pad) and disconnect the two wires connecting to them to access the brushes. Again, be careful with the wiring orientation here – usually, the positive (+) terminal is on the right, and the negative (-) terminal is on the left.

Unscrew the carbon brushes and check on the two-point surfaces to ensure they are making contact. If they seem to be making enough contact, then the problem is with the stator itself. If there is no contact, they are worn out and replaced with new carbon brushes.

d) Loss of Residual Magnetism

Another common culprit of the generator not producing power is the loss of residual magnetism in the alternator, at least for those models that use electromagnetics.

What is residue magnetism anyway? The amount of magnetism left when the generator shuts off, and it’s necessary for starting the power production next time you run the generator.

If the magnetism was lost, the generator will usually start but will produce low voltage or nothing. It will require you to introduce some electricity to kick-start the electromagnetism responsible for restoring the residual magnetism.

When Can a Generator Lose Its Residual Magnetism?

  • If it has been sitting unused for extended periods
  • If allowed to run out of gas, especially when the load hooked up
  • When you turn its engine off while the load is still on.

How to Restore Lost Residual Magnetism

There are three methods that you can use here:

  • Use a hand-drill
  • Use a 12-volt battery
  • Use a jump start kit

Using a Corded Drill to Restore Lost Residual Magnetism

Go to your garage or storage and take out the working corded drill (if you have one). Then, with the generator on and running and the AC off, hook it up to one of the 120-volt AC outlets on your generator panel.

Set your drill to the forward position in a way that the chuck turns clockwise when holding the drill handle and hold it away from you.

Press the trigger and spin the drill chuck in a backward direction (counter-clockwise direction) – the drill chuck MUST be empty to avoid accidental injury when the generator starts to produce power, in case it does.

Try to spin the chuck in a fast, flicking motion to trigger enough current. Give two to three twists. Your drill might start working right from your hands if the residue magnetism was restored.

Using a 12-Volt Battery or a Jump Starter Pack to Restore Lost Residual Magnetism

You need first to gain access to the alternator brush terminals. Next, open the stator cover by unscrewing two or three screws holding it.

Once you access the inside of the stator, unscrew the AVR and disconnect it from the quick connector. Next, disconnect the two spade connectors connecting the AVR to the brushes.

Remember to check the polarity of the two terminals – mainly, the red (+) terminal is on the left, and the black/white (-) is on the right.

Take a 12-volt battery (even your car battery can do the trick) or a jump starter. Connect the negative battery wire (black) to the negative (-) brush terminal and start the generator.

While the generator is running, connect a load (a light bulb will do just fine) and connect the positive wire to the positive brush terminal.

Is the light bulb lighting? If yes, congratulations. You have to restore power in your generator.

e) Faulty Capacitor

Brushless generators use a capacitor instead of brushes. The capacitor is responsible for introducing voltage into the rotor and also regulate voltage output.

A faulty capacity would result in low or no voltage output. If you get low voltage, something will come from the residual magnetism, something between 2-5 volts.

How to Test If Your Capacitor is Faculty

Locate the capacitor using your generator manual. Then, remove it from the generator and discharge it. A charged capacitor is dangerous and potentially hazardous – it’s crucially essential you discharge it.

So how do you discharge it? Take your flat-head screwdriver (with an insulated handle) and connect both capacitor terminals. You should hear a loud pop or a spark. It only takes one short-circuiting to discharge it.

Once discharged, use the multimeter (set to capacitance) and take the capacitance of the capacitor. It should be +/-5uf of what is written on the capacitor side. If it’s lower, get a capacitor replacement compatible with the generator (from your generator manufacturer) and replace it.

Generator Still Not Producing Power? Seek Professional Help

If none of the above troubleshooting techniques helped restore power in your generator, it’d be best to seek some help from a qualified generator technician. If your generator is under warranty, you have the option of not even touching anything and shipping it back to the manufacturer.

But if you’re past the warranty period, you can seek the services of a local generator technician. The expert can help you figure out the problem; mostly, it’d be insider the alternator and what to do next.

Final Thoughts

Why is my generator not producing power? It might be it has a tripped or faulty breaker, defective AVR, lost residual magnetism, or faulty capacitor. As you can see, you can solve all these with simple DIY skills and readily available tools. However, at times, the problem can go deep in the stator or alternator as a whole. Therefore, it’d be best to take the generator to an expert to check for such a problem.

About the author

Sharif Gen

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