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fusing relays

fusing relays

fusing relays

(OP)
When selecting a 220vac relay, I notice that htey all have an extremely low current rating...generally around 9mA...are these generally fused?  Using the max fuse size of 300X doesn't even come near the typical low fuse value of .063 (1/16a).....I'm swiching the relay on through a limit switch...

RE: fusing relays

Normally the fuse is intended to protect parts of the system or equipment upstream of the fuse, not the connected load. Go with a 100mA or 250mA fuse. If the relay goes bad the fuse will blow. Very low current fuses are usually bad news because they are vulnerable to physical shock damage.

----------------------------------
  Sometimes I only open my mouth to swap feet...

RE: fusing relays

Why do you think that you need a fuse at all?

Fuses are never, ever used the way you are going to use them.

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: fusing relays

(OP)
I will not use a fuse....I didn't think I ever saw one in such a situation....I was not thinking.....basically, the coils will not draw much more than 25ma....
Once again you've helped me, thanks....

Mark

RE: fusing relays

you use a voltage style relays, and its work requirements are around 60% of 220 VAC, and over 9 ma. please check the mannual again, coz I think the contacts of the relays must can support over 5AAC, whatever is the working current ot tripping current. they are differnt, or you can try to contact the company which produces the relays.

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