Light Bulb Wattage Question.

[Twista]

When i DIM the lights i can hear a buzzing sound coming from the light bulbs. The sound goes away when i turn the dimmer to full power.


Do i need different type of light bulbs?

-------------------
I was just brought a dimmer light switch (rotary). It says 120v/600 W on the switch.

Does that mean the max wattage light bulb that can used is 60 watts? Or can i buy a 75w or 100 watt bulb and have no problem.


Thanks

 

[KLin]

Originally posted by: Twista
I was just brought a dimmer light switch (rotary). It says 120v/600 W on the switch.

Does that mean the max wattage light bulb that can used is 60 watts? Or can i buy a 75w or 100 watt bulb and have no problem.


Thanks

You should be able to use up to a 600W bulb.

 

[Twista]

thats what i thought. I was having problems installing it and looked up a site on google. It said something about 600 watts = 60w. So, that is what confused me. Thanks.

 

[randay]

or 10 60w bulbs...

 

[Twista]

Also, when i DIM the lights i can hear a buzzing sound coming from the light bulbs. The sound goes away when i turn the dimmer to full power.

Do i need different type of light bulbs?

 

[SunnyD]

Watt?

 

[JJChicken]

Originally posted by: Twista
Also, when i DIM the lights i can hear a buzzing sound coming from the light bulbs. The sound goes away when i turn the dimmer to full power.

Do i need different type of light bulbs?

I don't know if this is a joke thread or not, but assuming it isn't, the buzzing is coming supplying too little wattage to your light bulbs.

 

[spidey07]

Dimmers are notorious for making a hum in stereos/home theater. Check and double check your grounding and wiring of the dimmer. Don't know if they're related.

 

[daveshel]

The 600W rating means that is the maximum amount of power the dimmer can dissipate. If you're using a 100W light bulb and the dimmer is wide open, the dimmer is dissipating 0 watts. If the 100W is being totally dimmed, the dimmer is dissipating 100 watts - turning it into heat. So if you were to exceed the 600W rating, it would get hot enough to start a fire.

Is the buzzing sound coming from a compact fluorescent lamp? They should not be used with dimmers.

 

[BigJ]

Twista,

The rating of the dimmer is the maximum allowed wattage that it is approved for at a certain voltage. That means all the lights on the circuit the dimmer controls can add up to, but not exceed, the 600w.

However, this does not mean you can use any bulb you like in the lamps you are controlling. I'm assuming you have recessed lighting? If so, there will be a rating on both the trim (the decorative outside part of the recessed light) and the actual can. You can use a bulb up to what those two specify.

Is the dimmer itself buzzing or are the light bulbs buzzing?

EDIT: I see the bulbs are buzzing. I would recommend replacing your current bulbs with higher quality bulbs and see if the buzzing persists. Do not use Compact Florescents with dimmers unless the bulbs are rated for dimmers.

 

[Red Squirrel]

Think it's normal, I've always noticed dimmed light bulbs make a noise. Some people state they can't hear it though. when I had a CRT if the dimmer in the kitchen was dimmed the CRT would also do the buzz noise from the noise on the line. AFAIK dimmers don't actually lower the voltage, they just time slice, it's like flicking the switch on and off very fast. Think it also goes with the AC phase, hence why the buzz is 60hz.

 

[KLin]

Damn, and I was hoping to put a 600w bulb on one. 🙁

 

[NL5]

You don't need new lights, you need a better dimmer. Cheap dimmers work by clipping the waveform, and cause massive harmonics, hence, the buzzing.

 

[BigJ]

Originally posted by: NL5
You don't need new lights, you need a better dimmer. Cheap dimmers work by clipping the waveform, and cause massive harmonics, hence, the buzzing.

The reason I recommended the lights over the better dimmer is because it's going to cost quite a bit more to get a quality dimmer than it would some better light bulbs.

Most people don't want to do it right when it's going to cost them.

 

[Howard]

PWM could be causing the elements to vibrate.

 

[JohnCU]

well shit since when did dimmers come with SCRs? i thought it was just an increasing/decreasing resistance. fuck they don't teach you anything in school

 

[Amoreena]

Originally posted by: daveshel
The 600W rating means that is the maximum amount of power the dimmer can dissipate. If you're using a 100W light bulb and the dimmer is wide open, the dimmer is dissipating 0 watts. If the 100W is being totally dimmed, the dimmer is dissipating 100 watts - turning it into heat. So if you were to exceed the 600W rating, it would get hot enough to start a fire.

Is the buzzing sound coming from a compact fluorescent lamp? They should not be used with dimmers.

Completely false.

The dimmer uses a Triac and only sends a portion of the sine wave to the bulb. You are thinking that the dimmer uses a pot as the power controller, which is not true. Look up phase control Triac circuitry FTW.

 

[DaveSimmons]

Blackouts, buzzing in your head -- sounds like it's time for you to cut back on the drinking.

 

[Evadman]

Originally posted by: daveshel
If the 100W is being totally dimmed, the dimmer is dissipating 100 watts - turning it into heat.

What? No. There is no dissipation in the dimmer, the dimmer is not a resister.

 

[PlasmaBomb]

Originally posted by: Evadman

Originally posted by: daveshel
If the 100W is being totally dimmed, the dimmer is dissipating 100 watts - turning it into heat.

What? No. There is no dissipation in the dimmer, the dimmer is not a resister.

Early dimmer switches were variable resistors 🙂

Modern ones use a triode alternating current switch (and some other electronics).

If you hook up a really cheap dimmer switch, you can get a buzzing noise, due to vibrations in the bulb filament caused by the triode alternating current switch.

Edit: Actually its caused by the effects of the Triac when it starts conducting and causes a larger than normal change in the voltage, resulting in changes in the magnetic field around the filament.

 

[ElFenix]

Originally posted by: Amoreena

Completely false.

The dimmer uses a Triac and only sends a portion of the sine wave to the bulb. You are thinking that the dimmer uses a pot as the power controller, which is not true. Look up phase control Triac circuitry FTW.

are you rubycon's daughter?

 

[PottedMeat]

Originally posted by: JohnCU
well shit since when did dimmers come with SCRs? i thought it was just an increasing/decreasing resistance. fuck they don't teach you anything in school

A really long time. All they need is a large value pot, diac, and a triac. I'd hate to have a 500W+ low value potentiometer mounted in my wall as a dimmer.

 

[PlasmaBomb]

Originally posted by: ElFenix

Originally posted by: Amoreena

Completely false.

The dimmer uses a Triac and only sends a portion of the sine wave to the bulb. You are thinking that the dimmer uses a pot as the power controller, which is not true. Look up phase control Triac circuitry FTW.

are you rubycon's daughter?

Damb how did I miss that 🙁

 

[us3rnotfound]

Originally posted by: JohnCU
well shit since when did dimmers come with SCRs? i thought it was just an increasing/decreasing resistance. fuck they don't teach you anything in school

I definitely agree. I'm a junior in EE and I wasn't aware of this either.

Edit: but my friend who's a EET did. I knew I should have just gone for that degree.

 

[NL5]

Originally posted by: us3rnotfound

Originally posted by: JohnCU
well shit since when did dimmers come with SCRs? i thought it was just an increasing/decreasing resistance. fuck they don't teach you anything in school

I definitely agree. I'm a junior in EE and I wasn't aware of this either.

Edit: but my friend who's a EET did. I knew I should have just gone for that degree.

Wow. It was like day three of electronics 101.