Shop light

[Peter LR]

Hi everyone! I'm a newbie, as regards solar. My wife and I just finished building a gym (12x20 shed), and we set up some shop lights that we bought from Amazon. They came in a pack of 6, but we're only using three. I have them set up, and I installed a light switch, that connects to an outlet, so that I can simply flick on the switch and the lights are there. It's really nice. However, I noticed that there is a hum to the lights, when I turn them on. It doesn't do that, when I run a long extension cord to the gym and connect the lights that way (I was curious one day).

I'm thinking that it's the voltage level (only 12V battery). Is the humming dangerous, or is it simply an annoyance? I plan on setting up a beefier solar system (perhaps 24V), as we get more things, but for now, it's only a 12V system.

Thanks for any thoughts you can share.

 

[Jim Burrow]

If these are fluorescence bulbs, they are famous for humming. Also if you are only using two-wire to connect the bulb from the switch, you may have to run a third green (green standard for ground wire) to the ground. when you hear a 60 cycle hum it is sometimes a loose wire but quite often a bad ground and this is called a grounding loop. this means there is a voltage potential between your fixture and the ground cause a voltage potential difference.
anyway, it's a starting point. - Note that your extension cord could already have a green grounding wire in it and is grounding your fixture, hence eliminating the hum.

 

[Hedges]

120V shop lights. Extension cord or <something else>
Is that something else an inverter, running on 12V?
Pure sine wave or "modified sine wave"?

If modified, it's harmonics might be the source of noise.

 

[Jim Burrow]

What's called dirty voltage or current, like Hedges said could be the problem too. I do know that fluorescent tubes will hum like crazy. It's probably not so my the bulb as it is the fixtures or at least the cheap one. But LED bulbs to the rescue!

 

[Jim Burrow]

What's called dirty voltage or current, like Hedges said could be the problem too. I do know that fluorescent tubes will hum like crazy. It's probably not so my the bulb as it is the fixtures or at least the cheap one. But LED bulbs to the rescue!

A test you can do. Go to lowes or home depot and buy one of the $15 or $20 LED light fixtures and see if the hum goes away. I now have all LED shop lights in my workshop. Love them and they are bright and use around 9 watts per fixture. - just an idea!

 

[JoeHam]

The link in the first post shows these are LED lights.

Are they powered from an inverter or generator or .........

 

[HRTKD]

I have 5 LED shop lights in my garage and they don't hum. At least not that I notice. Mine are similar to the ones in the original post.

Maybe a MSW inverter is being used instead of PSW?

 

[Peter LR]

120V shop lights. Extension cord or <something else>
Is that something else an inverter, running on 12V?
Pure sine wave or "modified sine wave"?

If modified, it's harmonics might be the source of noise.

Hi there! Should have put this before but my 3000W inverter is what's powering the shop lights

 

[Peter LR]

The link in the first post shows these are LED lights.

Are they powered from an inverter or generator or ........

The link in the first post shows these are LED lights.

Are they powered from an inverter or generator or .........

Hi. Here is my 3000W inverter.

Thanks.

 

[schmism]

However, I noticed that there is a hum to the lights, when I turn them on. It doesn't do that, when I run a long extension cord to the gym and connect the lights that way (I was curious one day).

The harbor freight inverter is a modified sine wave inverter. The hum you hear is likely the inverter powersupply in the lights reacting to the modified "sign" wave output of the inverter. Running off the extension cord run from grid is nice clean stable sign wave.

 

[Peter LR]

Thanks! There's no harm to the light though, correct?