How to Eliminate Inverter Noise

As an Amazon Associate, this site earns commissions from qualifying purchases. For more details, click here.

Have you ever heard a high frequency sound coming from your inverter? How about a knocking or some kind of buzzing noise? There are many possible reasons for those, and this guide shows you how to remove those inverter sounds.

Inverters usually produce a humming sound, but it is barely noticeable throughout the day. If the inverter is making loud knocking noises or a high frequency pitch, it means the battery cable is too small and unable to supply enough power to the system.

Do Solar Inverters Make Noise?

The majority of inverters make a humming noise when running a load. But the sound should be only audible if you are in the same room and it is very quiet. Ambient noise should drown it out under normal situations.

If you can still hear the sound it means there is something wrong with the system. Follow these steps to help you figure out the cause and how to permanently remove the noise.

Note: the following solutions involve inspecting and replacing cables and wires. If you have no experience handling electrical components, consult a professional electrician or your installer.

How to Stop High Frequency Sound From Inverter

The high pitching sound may come from the inverter or one of the appliances. Assuming the appliance is running but still producing the noise, the problem lies in the system.

Cause. The most likely reason is an incorrect battery cable size. As explained in another post, inverter to battery cables have to be the right size to work.

The high pitch sound indicates there is not power going into the inverter. The incorrect size has resulted in a voltage drop and is now affecting the inverter’s performance.

Solution. The rule of thumb is use the thickest wire gauge available for your battery inverter setup. Check the owner’s manual for recommended wire sizes and choose the thickest one allowed.

The battery cable must also be as short as possible. If you can keep the cable length to 10 feet or less, great. This solution also works for solar panels.

What if your inverter has been running for a while and suddenly emits a high frequency sound? If you are sure the wires are the right size, they could be frayed or worn out. Inspect the wires and replace if necessary.

How to Stop Loud Inverter Beeping Noise

The beeping sound can indicate different things depending on the inverter type. The following are some of the possible causes and solutions.

Beeps every 5 seconds: the system is experiencing low voltage
Solution: make sure the cable is the correct size. Replace the cable if required. Look into the battery and make certain there is enough capacity.

Beeps continuously for 60 seconds: the beeping then stops and repeats after a few hours.
Solution: this signifies battery failure. The inverter tests the battery regularly, and the beeping sound means the battery did not pass the test. Replace it immediately.

Single beep or four beeps every half minute: the inverter has switched to battery mode.
Solution: this is not a problem per se. if you are off the grid the inverter will always draw power from the battery.

Beeping could also be a sign of system overload. Inverters are designed to run a specific amount of power. If the system overloads or is near capacity an alarm will sound off.

Just as solar panels can overcharge batteries , it is possible for appliances to overload an inverter. Never run an inverter at the maximum capacity and always leave room for sudden power surges.

How to Stop Knocking Sound From Inverter

The knocking noise sounds exactly like that, a series of thuds coming from the system. In some cases it sounds like a soft knock while others resemble a banging noise.

Cause. The battery is running low and can no longer supply the power needed to run the load. The knocking or beeping sound is the system informing you.

Solution. Remove the load and recharge the battery. When the battery is charged, reload and run the system again. The noises should disappear.

Many inverters have an alarm to indicate when the battery capacity is low. But others do not. Moreover, the alarm only goes off when the battery is almost empty.

Most batteries like FLA should be recharged at 50% as full discharges shorten its life cycle. You need to calculate how many batteries your inverter needs while including the 50% discharge rate.

Once you know the inverter load and battery capacity, you can estimate how long before a recharge is needed.

Do not load the inverter to its stated limit. That is, if the inverter is 2000 watts, do not load 2000 watts into it. Some energy is lost when DC is turned into AC so the usable capacity is going to be 5% to 15% less than the capacity.

Even if you have a very efficient inverter, it is always better to leave some power in reserve in case the power suddenly spikes up.

Why is My Inverter Alarm Going Off?

There are many possible reasons for the alarm to sound. The most likely reason is the battery cable size is incorrect and not enough power goes through. It could also be an indicator the system needs to recharge or it needs maintenance upkeep.

The alarm could also be an indication of an internal problem. Monitor the inverter if it is running the load properly. If there is nothing wrong with the inverter, check the battery cable or the batteries themselves.

Manufacturers use different parameters that trigger off the alarm. Most will go off if there is overloading and overheating. But others will also sound off if the battery cable is damaged or voltage is low.

The best way to find out is to check the owner’s manual. You will see all the possible instances when the alarm will go off and why.

Other Ways to Minimize Inverter Noise

Solar inverters have come a long way since the early days of PV systems. Modern inverters have built in features to minimize the noise. Noise reduction filters, shields and sound cancellation elements are among the methods used. Try turning off the inverter and back on again.

Metal enclosures are often used to reduce noise, and shielded, twisted cables can also be effective. Noise cancelling filters are widely used though the filtering system used varies.

Condensers are frequently used to eliminate noise, but implementation differs from brand to brand. Other solar system installations use beads, cores or ferrite chokes to minimize sound emission.

Do Solar Systems Really Make Noise?

Almost all electronic components produce noise, though some barely audible to the human ear. Electronic interference is one of the most common causes.

If you hear noise coming from the PV system, check if it is really coming from the inverter or another component. Charge controllers for instance, transmit electrical pulses to batteries. A poorly designed controller might emit a loud noise during this process.

Other interference may come from power lines, radio waves, electromagnetic systems and some consumer electronics. If the noise is indeed coming from the inverter, inspect the configuration for the possible source.

Tips to Maintain Your Inverter Battery System

Most of the time the noise is due to the inverter, battery or both. It can be a technical problem or the system just needing maintenance. Keeping both in good shape helps reduce the noise..

  • Install in a well ventilated area. Batteries produce heat when running, especially FLA. With enough ventilation you can prevent clogging and improve performance. While the inverter should be installed near the battery, there should b some distance for proper ventilation.
  • Read and follow the instructions. Your inverter manual comes complete with all the do’s and don’ts’s, so follow it to the letter. If you are not sure, contact the manufacturer.
  • Clean the batteries and inverter. You can make batteries last longer LNK by cleaning, same with inverters. Make sure the terminals do not have rust and are not corroded.
  • Clear the vents. Do not allow dust to build up in the vents. That will trap heat in the battery and affect performance.

Conclusion

If you hear an unusual sound from the inverter, do not panic. Usually any of the solutions given here will be enough to fix it. Of course you should also look into the owner’s manual for more information.