What Causes a Portable Generator to Surge

Having a portable generator is a sure way of having electricity wherever you are. It can also act as your home power backup plan. But have you experienced flickering lights or unstable machine speeds when you rely on a generator for power? That occurrence is termed surging. The question would be, what causes a portable generator to surge?

Power surging from a portable generator is a sign that things are not running smoothly. This can lower the efficiency of your generator. You need to check what the problem is. Herein is a discussion of the most common causes of surging in a portable generator. But before that, let’s look at the different signs of a surging portable generator.

Signs That Your Portable Generator is Surging

what causes portable generators to surge?

The surging of a generator leads to power fluctuations which can occur randomly or at easily observable intervals.

Observable surging signs include;

  • Flickering of lights from being too bright to becoming dim promptly.
  • Drastic increase or decrease in speed of the generator’s fan for no discrete reason.
  • Unexpected change of speed in the machines you are powering.

What Causes a Portable Generator to Surge

The common reasons are;

1. Aging of a generator

what causes a portable generator to surge??

Even though generators are built to last for a long time, they don’t last forever. The internal components are subject to the normal tear and wear of machines making the generator likely to surge. While servicing and replacing the engine parts can be a temporary solution, the best thing to do is replace the generator with a new one. Otherwise, the issue will still come up even when you replace the interior components.

2. Poor Maintenance

Just like any other mechanical equipment, portable generators require regular maintenance for them to deliver optimal services. If you run your generator regularly, you should service it at least after 200 hours of running it.

While you can handle the maintenance services by yourself, dip servicing, repairs, and replacement of engine components should be done by a qualified technician. Poor handling of the engine parts by an incompetent party can lead to the slow death of your generator.

Disregarding your generator’s maintenance schedule increases the rate of wear and tear. Additionally, it can lead to more complicated problems, which causes surging. This can be avoided, right?

3. Fuel Problems

what causes a portable generator to surge

Generator surging problems resulted from fueling can happen because of;

  • Using incorrect fuel
  • Low fuel levels
  • Poor fuel quality
  • Faulty fuel pump

For your portable generator to perform at its peak level, it requires proper fueling. Most portable generators are made to run on a particular type of fuel. Using strange fuels can lead to operational problems, which can lead to surging.

Check on the fuel levels; if the fuel level in the fuel tank is low, the carburetor could be receiving insufficient fuel. This can result in surging and finally shutting down the generator. Always check the fuel gauge or fuel level in your generator before powering it on, and plan for a refill if the fuel level isn’t sufficient.

Poor quality fuel may mean contaminated fuel or overstayed fuel. Both are not good for your portable generator. If you store your generator fuel for over six months, you should get fuel stabilizers. Otherwise, putting old fuel in your generator can hamper its functioning and probably lead to surging.

A faulty fuel pump can lead to poor distribution of fuel to the engine. Power fluctuations are inevitable when there is an unreliable supply of fuel to the engine. One of the leading causes of fuel pump failure is fuel contamination. Fuel contaminants can easily block the fuel pump. One would also want to know, is there a portable generator that runs on natural gas?

4. Damaged Engine Components

what causes a portable generator to surge

If you are wondering why your portable generator is surging, spoiled components could be the reason. For instance, a damaged capacitor can hamper the generation and distribution of power, resulting in extreme power fluctuations in power output control. Damaged components do not necessitate replacing the entire generator, but you can replace the precise components. There is a need to understand about the different types of generators.

5. Unbalanced Load

A load of a generator can increase or decrease depending on the appliances you are powering. If your generator has three phases, you should ensure that all three phases have an equal share of the load. Similarly, it would help if you also ascertained that the generator is not overloaded. Overloading or having an unbalanced load can cause power spikes.

Installing an overload circuit breaker on your portable generator will protect your appliances from the effects of a power surge. In case of an overload, the overload circuit breaker will trip, disconnecting the power supply to your appliances.

6. Abrupt Start of Machinery

When you start are heavy machine running on a portable generator, there is a likelihood that there will be a power spike. In some instances, the big machine can cause a temporary drain in power from other appliances connected to the generator, which may not be noticeable. However, in situations where the appliance is plugged in is too much for your portable generator, you can witness the signs of a power surge. In worse scenarios, the generator can shut down.

7. A Faulty Automatic Voltage Regulator (AVR)

What causes a portable generator to surge?

It is a small gadget found on the alternator and is designed to monitor the output power of your portable generator. Its main job is to maintain stable voltage to the load on the generator. In other words, the AVR smoothens the stable output power of your generator. If the AVR is faulty or intermittent, it will not control the power output, which leads to a power surge.

8. Running Erratic Motors

These are motors that don’t have a constant speed. Such motors are the biggest reason for the power surge in portable generators.

Especially when the erratic motors do not have a speed governor or are old, the running of such machines can lead to a higher increase or decrease of power, leading to an unpredictable power surge.

Such power surges are dangerous to appliances connected to that generator. Overloading erratic motors to a portable generator can damage the generator.

What Should You Do When Your Portable Generator is Surging?

A surging generator can damage your sensitive electronics. Sensitive electronics are those electrical which have inbuilt microprocessors and other digital parts that are vulnerable to power fluctuations. Examples of these electrical include microwaves, TVs, computers, smartphones, and other household electronics.

Disconnect all power appliances connected to the generator and find out the causes of the power surges. If it is something you can resolve, proceed; if it’s beyond your abilities, contact a qualified generator technician.

Frequently Asked Questions

1. Can a Portable Generator Cause Power Surge?

Yes, a portable generator can result in power surges. Poor maintenance of your portable generator, use of improper fuel, overloading it, and normal wear and tear of a generator can necessitate the surging of a generator.

2. Is the Generator Surging Bad?

Yes, if a generator is running at its best, there will be no cases of surging. Generator surging means there is a problem with your generator. A surging generator can damage your vulnerable electronics. There is a need to make the portable generator power clean.

3. Can a Power Surge Damage Electronics?

what causes a portable generator surge?

Yes, during a power surge, the power rises more than is required. This rise can damage appliances connected to the power. In other instances, a power surge can damage the power outlets or cause a fire in a worse scenario.

4. Why is my Portable Generator Running Rough?

A clogged carburetor is one of the leading causes why your portable generator has a rough operation. The clogging of a carburetor occurs when you leave fuel in your generator for a long time without running the unit.

When fuel is left in your generator for an extended period, some constituents in the fuel evaporate, leaving behind thick matter which clogs up the carburetor. It decreases the engine performance leading to a rough operation. How to avoid this;

  • Ensure your generator does not stay with fuel for an extended period without running.
  • Regularly clean up the carburetor after extended usage; this will give the unit a smooth operation.
  • Avoid using overstayed fuel. This is the fuel that has stayed for more than six months.
  • If you are not using the generator regularly, run it once or twice a month for about 2 hours.


5. Are Portable Generators Safe for Household Electronics?

what causes a portable generator to surge

It will depend on the quality of the portable generator. Portable inverter generators are safe for powering household electronics, even the highly vulnerable electronics, including TVs and computers.

This is because inverter generators produce electricity that has less than 5% harmonic distortion. However, for ordinary portable generators, it is not safe to run sensitive household electronics.

Their power output can fluctuate and damage the electronics. If you have to power your sensitive electronics with such generators, consider using a surge protector.

Final word

Power surging from a portable generator is a red flag. It means that your generator is not running as it is supposed to. Some of the causes of a generator power surge include aging of the generator, poor maintenance, fuel problems, a faulty AVR, among other causes listed above.

Apart from the problem of the aging generator, you can solve the other causes of power surge from a portable generator by hiring a certified generator technician. Do not repair the engine components if you are not conversant with such repairs.


About Steve Stuart

Steve Stuart is an electrical engineer who developed interest on generators during his school years. After school, he became a generator enthusiast. This is after encountering power supply problems at the area of residence where he lived. Power would be on and off and so food would go bad and the room heater would go off especially during winter. After trying the different generator brands for several years, Steve now provides information on the available brands and products in the market today. Based on his experience, he gives the do’s and the don’ts when it comes to generator use.

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