Better than a MOV?

[#12]

I was designing a snubber and thought about using a MOV to clamp the voltage spike below 250 so I can use the 250 volt capactors I have, but a 130 Volt (Littlefuse brand) MOV limits voltage to about 220 volts at 1 milliamp. Obviously, the current spike when a Triac shuts off is way more than 1 milliamp.

Perhaps I am out of date. Can anyone name a device that has lower clamping voltages per amp than a similar voltage rated MOV?

ps, I'm in USA with 125V mains and 60 Hz frequency.

 

[KeepItSimpleStupid]

Search for "ZNR"

Digi-Key

 

[#12]

I looked, but the graphs don't seem to be saying this is an improvement, and very hard to read! Maybe that's the problem. The graph is so small that I can't be sure the Panasonic ZNR is better than the Littlefuse MOV for this purpose.

Thank you, but more suggestions would be welcome, like how to get that training chart in a PDF so I can expand it to readable size, or some other device that has been invented since the last time I researched this topic.

 

[#12]

Here's an idea...just forget the snubber, put the MOV across the 400 volt Triac, and expect that to keep it safe. Will that work?

 

[KeepItSimpleStupid]

You looked here: ZNR Transient/Surge Absorbers Series Type:V | ZNR Transient/Surge Absorbers | Passive & Electromechanical | Panasonic Industrial Solutions Global

Some versions have a 1.2kA surge ability.

Snubbers are used to limit dv/dt so the triac doesn't turn on when it's not supposed to.

 

[#12]

Thanks for the reminder about the dv/dt.

I looked at where you said. I downloaded the spec sheets and ran through the training manual.
Aha...found it. 30 milliamps at 250 volts.

I think I'm gonna have to buy 400 volt capacitors to snub a 400 volt triac instead of trying to force what I have laying around the shop to do what I want.