Leviton ViziaRF (and nonRF) Dimmers - Loud Buzz

[Scott12v]

I posted this in another thread, but wanted to include it here for completeness...

Well, I just installed one of the 1000W Vizia switches and am MUCH happier. My faith is almost restored!

There is a very minor buzz from the switch at the lowest dim level, but I can only hear it if my hear is right next to the switch. This is much different than the 600W switch that I can hear an audible buzz from several feet away.

The final test will be tomorrow when I move it up to the bedroom (where it is VERY quiet), but I'm pretty sure I won't hear it.

The 1000W switches are built differently than the 600W switches. They are a little bulkier and are wired differently (they don't have screw terminals, the wires are built in).

Scott

 

[slipnfall]

I'm new to the whole HA/lighting arena, but I can give my input on the electronics side. Most dimmers are as many know a small switching power supply. Rather than the dimmer dissipating the excess power as heat [and dimming the light], the input power is regulated down via PWM. The PWM signal typically drives a highly tuned inductor, cap, and usually a fast reacting diode. When the circuitry (providing the PWM) detects a lower load, it will switch modes of operation... sometimes skipping a pulse every so often to improve efficiency.

Basically the external passive components are only good for a small window of efficiency. What this means, in the end, is that 1000W controller is likely operating in a lower 'mode' than the 600W with your particular lighting situation. If the two were designed with the only difference being power handling capability, I would suspect the 1000W would do the same thing at an equivalent power level.

It's hard to get rid of all buzzing: you have to balance securing the component to the PCB and allowing it to cool properly.

Cheers,
Jamie

 

[slipnfall]

Oh and BTW, the noise in the bulbs is the filiment resonating from noise riding on the 60hz.

 

[ChrisWalker]

I also had a 600W dimmer that was buzzing audibly. I swapped it out for another 600W dimmer and the audible noise went away.

Just FYI, the dimmers do give off a very faint buzzing sound with some lighting loads--but this was an audible (i.e. not holding your ear up to the switch) kind of sound.

The 1000W dimmer has the same effect. It looks like I just got one (out of 80) in this batch that had a manufacturing glitch or something.

Overall, I'm pretty happy with the Vizia RF setup in this particular test home. With 4 bedrooms, 4 bathrooms, and 80 devices (not including any plug-in modules or receptacles), it's working very nicely.

Chris

 

[Squintz]

Sorry to bring up such an old thread but I'm experiencing this issue with a customer. I installed 40 600 watt dimmers for them and they all seemed fine when I left the job site. I got a call for an unrelated issue a few days later and while I was there fixing that I noticed that one of the switches in the basement was buzzing really loud. I replaced that switch with another 600w and everything was fine. I just got an e-mail from the customer yesterday saying that now 3 of their switches(or bulbs) are buzzing.

It seems from this thread that the problem has be narrowed down to a simple manufacturing issue and simply replacing the switch with another should solve the problem.

Has anyone else had experience with this issue and what were your results? I'm trying to save hours of troubleshooting by coming armed with information.