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Are metal body toggle switches safe for mains switching?

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gabri.peic:
Hi. I am building a vintage style amplifier and I would like to use a toggle switch as a power switch. I could put it on the secondary side of the transformer but than the transformer would be on whenever the thing is plugged in. It would be the best if I could use it as a hard power switch.
But I am worried about the safety of these metal toggle switches... So are they safe to use for mains???
Obviously I would use high quality one and ground it to the metal front panel of the amplifier.

Ian.M:
If from a reputable manufacturer, and rated for 250V AC, and your transformer's inrush current, yes they are safe when mounted to a grounded panel.

CaptDon:
Well, one would assume so since they have been on almost every amplifier ever made? It should/must be used on a GROUNDED metal panel. If you are a musician you should always have your amplifiers grounded, even more so when playing outdoors. When I play outside I am usually barefoot (kind of a trademark actually) and I have had some serious electrical burns on my lips when I got against a microphone of an ungrounded sound system that was plugged into a receptacle with no ground. The 'hot' wire was touching the metal shell of the receptacle box and putting 120vac on the 'ground'. I have also gotten zapped by the strings on my guitar when the whole 'front line' (lead player, rhythm player, bass player) was plugged into a power strip with the ground pin missing (cut off actually) and the bass amp had a shorted noise suppression capacitor from line to chassis. If the power strip was properly grounded it would have tripped off. BE SAFE!!!

TimNJ:
The timing of this post is pretty absurd. I'm building a little plastic test fixture box which with a number of AC mains switches. Yesterday, probably for the first time ever, I wondered "huh, what if the metal bat on one of these switches fails...can it easily become connected to mains?". So, did a quick search on Youtube to see how toggle switches are fundamentally constructed to try to understand the implications of a failure.

Found this video:
 

In the end, I think it really depends on the exact switch you are using. With a hard enough blow directly into the top of the metal bat, seems like the "plastic actuator thing" could possibly get crushed enough such that the metal bet comes in contact with mains. In normal use, if the "round nubs" get worn out enough that they break, you're probably safe because there's still the rest of the plastic rectangular thing still intact. This is solely referenced off of the above video.

At any rate, if you want to use a toggle switch without a properly earthed enclosure, probably best to pick a plastic paddle version.  ;)

Ian.M:
.... with a plastic bodr, boss and mounting thread.  ;)
Alternatively, if it has a metal body, and you are fitting it to an insulating panel, make sure the body is reliably grounded.

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