Dimmer hum

dakotapod

dakotapod

Veteran
I have 3 Smith Victor quartz lights [ 600 watt per ]. When I use an inline dimmer the bugger hums. The dimmer is home made using a home depot dimmer - Is this because of the dimmer or type of light? Would a better dimmer stop this?

Thanks
 
The type of dimmer that you are using is based upon a technique known as back slope regulation. These can be very noisy but they are inexpensive. A much better approach is to use an autotransformer (aka Variac). These are silent in their operation. Besides their step down (dimming) capabilities, Variacs can also act as a step up device. This can be a very handy feature if you have a low mains condition situation.

http://www.variac.com/
 
Thanks - let's pretend for a minute my brain is half the size of yours... :cheesy:

What is this autotransformer you speak of? Is this just used in dimmers specifically made for pro lighting or can I pick this up and replace the switches I'm using? I made 3 of these and it would be nice not to just toss the efforts.

Thanks again
 
Variacs are expensive.
quality dimmers are expensive
if you're going to make a career in this business, get use to hearing the word "expensive".
 
Thanks pookie. So my little brain says I'm making the filament vibrate?... Will using a 1k dimmer switch help? Using 600w now - Or are all the store bought dimmers going to cause this? Can't have the buzzing.

Edit: Don't mind buying real dimmers at all if need be. I just read a dozen posts over time saying these work fine so I built them...
 
I found this, it might help.

"Buzzing bulbs (dimmers) are usually a sign of a "cheap" dimmer. Dimmers
are supposed to have filters in them. The filter's job is to
"round off" the sharp corners in the chopped waveform, thereby
reducing EMI, and the abrupt current jumps that can cause
buzzing. In cheap dimmers, they've economized on the
manufacturing costs by cost-reducing the filtering, making it
less effective. Perhaps the dimmer will be okay at some
settings, but not others. Or be very picky about what bulbs to
use."

I follow what khmuse is saying, but I'd say you just need better dimmers, but I don't think you need to go quite as high as those he's linked.

Home Depot has the right kind for what you're after.
 
I've used a Lutron T-1000 Industrial dimmer that I bought at a Rona. Most lamps I've used it with have been buzz free. Hope this helps.
 
Pookie and Barry Cheong are right. I have dimmers built with consumer available dimmers and they work fine. I also use to work at a grip and lighting shop and we had the Variac dimmers, mucho dinero, but we also built our own with stuff from home depot.
 
You must log in or register to reply here.
Back
Top