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What does the 'H' mean?

What does the 'H' mean?

What does the 'H' mean?

I'm looking at the plate on a switch and I see multiple ratings on the front:
1/4 H.P. 120-240 V.A.C.
3A-240 V.A.C.
13A-120 V.A.C. (H)

On the back, a stamp reads:
6A-120 V.A.C.

I'm interested in why the multiple 120VAC ratings for the same item, but I'm mostly interested in what the 'H' stands for (which I'm sure will answer the first part).

Dan - Owner

RE: What does the 'H' mean?

I found this:


An "H" rating denotes a non-inductive resistive rating. Ratings listed... may appear with the symbol "H" or with the words "non-inductive" or "resistive". "H" ratings are typically required for switches used in commercial oven applications.

Does that seem like the definition of the 'H' shown above?

Dan - Owner

RE: What does the 'H' mean?

Yep, I think you've got it there.

Now, about that other 120V rating... I don't know.

Keith Cress
kcress - http://www.flaminsystems.com

RE: What does the 'H' mean?

'Heater' ?

RE: What does the 'H' mean?

It's the control switch for an oil heater, so "resistive element" fits the bill. These switches are also often used, evidently, for small motor control (my guess is fans and the like).

I just wanted to verify the actual spec on this switch before spec'ing a replacement.

Dan - Owner

RE: What does the 'H' mean?

H= Heater
Heater =coil heater = resistive= non-inductive thumbsup

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