Are inverters loud? Yes and no it depends.

So lets talk about the amount of noise a inverter makes.

Now from our experience should it be roughly 50-55 db (decibels) this is perfectly normal? or is it?

We have recently had heated discussion online regarding inverters being loud during recharging and not so much when on load, this can be clarified in many ways.

Inverter trolleys themselves are not inherently loud, but they can produce noise depending on several factors:

1. Fan Noise – Most inverters have cooling fans that kick in when the unit gets warm. Some fans run continuously, while others are temperature-controlled, making them quieter during low loads. Much like computer fans are either via PWM type fans which runs when needed depending on the temperatures while others run straight from DC no matter the temperature its controlled by the voltage of the fan. Also smaller the fan the louder it can be and of course the design of the fans blades.

2. Transformer & Coil Buzz – Some inverters, can produce a humming or buzzing sound from the transformer or coils, particularly under load.

3. Battery Charging Noise – If the trolley includes a built-in charger, it might produce a humming sound while charging the batteries.

4. Battery Type – If your trolley uses lead-acid batteries, they might emit a slight bubbling or gassing noise during charging.

5. Load Type – The appliances connected to the inverter can also affect noise levels. Inductive loads like fans and motors may cause the inverter to produce more noise. Higher the load the louder it gets basically.

6. Build Quality – Some inverters tend to be noisier due to vibrations, loose components, or inefficient cooling systems. I.E Blocked vents can cause the fans to suck more air as its trying to keep a flow of air to cool the components.

Are They Loud?

Most inverter trolleys are not excessively loud—typically in the range of 30–50 dB (about as loud as a computer fan). However, if you’re sensitive to noise, it’s best to look for one with a silent or variable-speed cooling fan. To which we only know of ones controlled via apps like Ecoflow where you can limit the recharging speed based on the amount of watts you allow it to recharge i.e fast charge can be load but slow charge can be dead quiet. When it comes to trolley inverters have not seen this option on them sadly. As for Off-Grid or hybrid inverters there are some that offer control to a extent.

To break it down in a example with our Ecoflow Delta 2 with extra battery (times were bad in 2023 hey).

If the Ecoflow Delta 2 is recharging at 1500W its pretty much a jet engine… I’ll admit that was loud. to which we just turned on quiet charging which takes 4hours from low % on the battery and it was 500 Watts.
But if you using the ecoflow we noticed its still roughly 53-55 db when running an average load of 450 watts we did notice it was slighly louder using 600+ watts as said earlier the more load the loader it gets now we never really run it more than close to 700w or at least i don’t think we did unless we plugged in a hair dryer that ran well over 1000 watts. Now to note the Delta 2 can output without X-Boost 1800W so we using a 3rd of its output but if we did half or more yes this would get loader.

With trolley inverters from what we gathered from users the complaints were that its always on and they can hear it  at 55db roughly and louder when recharging this of course if it has fast charge to which is most likely recharging at a higher wattage than what it outputs so if your output is not even half yes it may not be loud in comparison to recharging which can or could be using more than half to recharge (Dependent on model)

The one thing to note is that some inverters including portable power stations the fans are very basic and some are small the issue some face is that smaller fans equal louder fans but if they built them with larger fans and maybe better airflow pathways they wouldn’t be as loud.
That being said we tested 2 inverters that we notice however failed to read their DB.

Kool energy 1kva with a gel battery (we changed it to lithium) was very quiet i actually think as lower than 50db to be honest and even with a load of about 180w barely heard it, you can hear its on but barley in terms of sound.
While a while back we were testing a clients faulty Mecer 2kva lithium battery in use was fairly normal in terms of sound but on recharging we found it to be quiet loud as well little too much if the TV is on that and we depleted it quiet load before hand.

Sound is subjective

This being said something loud for you is quiet for me and vice versa this all depends on you and not saying hard of hearing just in general some people are sensitive to sound some are not, while coil buzzing can give someone a headache as they are sensitive to the sound to which doesn’t affect everyone much like a TV screen the light may bother some but not all (that’s another story all together).

Another example is a Car now there are the obvious ones that are loud and that are quiet, example
a V8 supercharged Jeep Trackhawk will rev at 3000 RPM at the DB of 90-110db give or take and they always fun to watch. (No we don’t own one)
and a Electric car will be whisper quiet. Looking at your Mini cooper that overtook me all we heard was whiiiisshhh passed us.

now that being said lets say you take a 1.5L Turbo petrol engine one can be whisper quiet while another you might hear it a bit more ever so slightly like the Biac X55 we find it very quiet for a 1.5L turbo (tiny engine must say). while a 1.4L petrol engine you can hear louder on a Peugeot 207 yes different tech different engine but all the same. Unless you get diesel they all have that clucking sound..

Overall

Sadly the db isn’t part of the spec sheets description this would of been nice but sadly none of these manufactures state these that we know of. However you can run a lead and run them from another room or at a distance, Or while Load shedding is suspended store them (Do check manuals regarding that before you store them).  There is no great answer to this question what irritates some doesn’t to others etc. Unless you want to spend 100k + on taking your home off grid where the inverter sits in the garage to power your whole home this option isn’t for everyone.

Can you modify the fans on a inverter probably but not recommended as you would void the warranty.