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Why Does Your Generator Keep Losing Magnetism?

Why Does Your Generator Keep Losing Magnetism?

With the rise of hybrid work, generators have become must-haves, especially in areas where electricity is intermittent. In some cases, however, generators seem to lose magnetism quite often, and the reason may not be apparent.

Usually, a generator loses magnetism if a load is connected to it when it’s not turned on or when you turn it on without connecting any load. This could also be the case if your generator has been left unused for a long time.

The following sections will dig deeper into how generators can lose magnetism over time and provide insight on how to fix them.

1. The Generator Has Exceeded Its Shelf Life

When operated correctly, residual magnetism typically remains within the generator even after it has been turned off. When it’s time to use it again, the generator produces little electricity through this leftover magnetism, and, in turn, this faint amount of electricity produces electromagnetic force. The generator engine magnifies the electromagnetic force until it produces power strong enough to provide the generator’s promised load capacity.

However, there is a limit to how long you can leave your generators turned off. Over time, the generator’s leftover magnetism will dissipate until there’s nothing left to produce the necessary amount of electricity to trigger an electromagnetic force. When this happens, you won’t be able to use your generator until external electric ignition is used.

Ideally, generators shouldn’t be kept unused for more than 2 weeks to ensure they can function optimally in times of actual need. Running them for a few minutes at a time will be enough to ensure they will be ready to provide power when needed (source).

While running your generators regularly may seem tedious at first, these machines can only be dependable when they’re well-maintained. Running them even just for short durations at least twice a month assures you that they are in good running condition and also spares the parts from corrosion, blockage, and possible loss of magnetism.

Remember that mistakes in handling generators don’t just happen while they’re running. The very act of not using your generators for long periods exposes you to risks such as not having your primary source of backup power at its optimal state during emergencies.

2. The Generator Was Operated Without Connecting Any Load

Generator load pertains to the amount of power you draw from your equipment. This is equivalent to the total energy requirements of all appliances running on generator power over a period of time. A common misconception about generator loads is that you’ll be able to extend your equipment’s useful life when you use lower loads relative to their maximum capacity.

The truth, however, is that when your generator is kept running without load or when the load is way lower than the machine’s maximum capacity, then your device may stop running correctly. One of the most common reasons would be the loss of residual magnetism.

Depending on your generator type, the prescribed load may vary between 50 and 100%. Standby generators are recommended to bear no less than 50% of their total load capacity. Meanwhile, Continuous-rated and natural gas generators need to maintain at least 70% of their load-bearing capacity for optimal performance (source).

Checking your generator unit’s minimum load requirement helps ensure it doesn’t lose its residual magnetism and that it will function when the time comes. 

3. The Generator Was Connected to a Load Without Being Turned On

To prevent your generator from losing residual magnetism, you should also make sure to shut down the equipment properly. Turning off the generator before disconnecting all appliances drawing power from the machine may damage the generator. You may find your generator isn’t able to start up by itself the next time if you don’t shut it down correctly (source).

As mentioned earlier, residual magnetism produces a small amount of electricity amplified by the engine to supply you with sufficient power. When you turn off the generator while your appliances still depend on it for power, the load will suck out what little electricity is left on the machine, leading to the complete exhaustion of residual magnetism. 

Hence, another step to ensuring that your machine always has some leftover magnetism is to unplug all connected appliances or transfer them to a different power source before turning the generator off. 

This may be a little bit confusing, as we also previously discussed that generators cannot run without load. In reality, running them without load for less than 15 minutes is not likely to cause you any problems. Hence, you have enough time to unplug your appliances first before shutting down the device.

What Is the Role of Magnetism in Generators?

Magnetism is a crucial element in making generators work. Electromagnetism allows electricity to flow from your generator into the connected appliances. When a generator loses magnetism, it also loses its overall capacity to function as well.

Unlike corrosion, however, loss of magnetism can only be temporary, so there’s no need to replace your generator immediately when you notice such a problem. Still, common misuse of generators that lead to a loss in magnetism may also be the same ones that lead to the breakdown of other machine parts, so it is important to avoid the scenarios listed above.

How Do You Fix a Generator That Has Lost Magnetism?

Fortunately, the loss of magnetism is not permanent, and it can be reignited by using a battery with the correct voltage and current specifications. Turning the generator off and connecting it to a battery will do the trick.


Proper handling and operation are crucial in keeping your generators in optimal condition. When your generators fail to provide electricity, it may be because they have lost their residual magnetism. Another possible cause is leaving a load connected to the generator while the generator is turned off or turning the generator on when no load is connected.

Fortunately, such a problem can be fixed by simply connecting your generator to a battery and reigniting its magnetism while it’s not in use.

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