ballast hum

[jes25]

I had a service call where I needed to change an old magnetic ballast. The replacement hums not real bad but it hums. Now the old ones throuhout the building do not hum. I checked the ground and replaced the replacement with no change in the hum. My question is why would the new ballast hum if the old do not. This is not a sign of a problem is it?

 

[infinity]

Re: ballast hum

Does the new ballast match the old lamps?

 

[jes25]

Re: ballast hum

That I thought of. The new ballasts calls for 40 watt but the guys at the supply house said it would work with the energy saving 34 watt. Could this be the cause if the hum.

 

[ron]

Re: ballast hum

Ballasts have a sound rating A, B, C and D.
Be sure you picked an A.
http://www.universalballast.com/techSupport/troubleshooting_guides/lin_g.html

 

[peter d]

Re: ballast hum

Originally posted by jes25:
The new ballasts calls for 40 watt but the guys at the supply house said it would work with the energy saving 34 watt.

The ballast should have a lamp compatibility chart on the label.

 

[Physis 2]

Re: ballast hum

I wasn't aware that ballasts had a noise number. That explains complaints about Home Depot fixtures.

I'm not very surprised that a new ballast would be noisier than an old one. I'd actually expect it. Quality anymore, forget about it.

I would'nt expect any noise from an electronic ballast. I prefer to upgrade to T-8 instead of just changing the ballast if its a T-12.

I'm just curious, has anybody had noise problems with T-8 or electronic ballasts?

 

[jes25]

Re: ballast hum

The ballast I selected had the best sound rating. I guess thats just what it does. I did suggest the electronic ballast.

 

[tshea]

Re: ballast hum

Originally posted by Physis 2:
I prefer to upgrade to T-8 instead of just changing the ballast if its a T-12.

How do you justify 1 fixture in a group of 10, 20 or 30 or more??

[ September 29, 2005, 04:26 PM: Message edited by: tshea ]

 

[peter d]

Re: ballast hum

Originally posted by Physis 2:
I'm just curious, has anybody had noise problems with T-8 or electronic ballasts?

Well, as a matter of fact, yes. I had a shoplight with a t-12 ballast that died, so I converted it to t-8, and indeed is does have a slight hum. Nothing compared to a t-12 hum, but it hums nonetheless. I don't know why because I thought it was pretty hard for humans to hear 20 KHz.

 

[dana1028]

Re: ballast hum

Originally posted by Physis 2:


I'm just curious, has anybody had noise problems with T-8 or electronic ballasts?

Yes, I just installed a customer supplied new Home Depot fixture with T-8s and it hums quite loudly. I plan on going back next week and replacing the ballast (non-Home Depot).

 

[Physis 2]

Re: ballast hum

By Tshea:

How do you justify 1 fixture in a group of 10, 20 or 30 or more??

When I've worked for EC's with larger commercial accounts a lot of them were replacing any failures, whether tubes or ballasts, and some areas in the buildings with T-8 to get the energy usage down. The only difference is that you replace the tubes too. The fixture stays the same.

It would figure that Home Depot could find noisy electronic ballasts.

Edit: the electronic ones still have some stuff on 120v. before it gets turned into the output.

[ September 29, 2005, 11:38 PM: Message edited by: Physis 2 ]