Re: a question about relays

On Sat, 9 Apr 2005 13:43:14 -0700, "Larry Brasfield"
<donotspam_larry_brasfield@xxxxxxxxxxx> wrote:

>"B Ghostleader" <VE7UFP@xxxxxxxxx> wrote in message
> news:128d68a8.0504091237.44584510@xxxxxxxxxxxxxxxxxxxxx
>>I have a project that I would like to control two relays with one
>> swiich. Is this possible? I was going to use a DPDT relay but that
>> price is a little steap for the current rating that a I needed(25 amps
>> min). I can go down to the local automotive store a get a 30 amp relay
>> for 5 bucks.
>
>The problem you will have, if you do that, is that
>only one relay will actually do the work of breaking
>the current. The other will open first, with little wear
>on its contacts. Then the other will open, and have
>to break more than its rated current to do so. One
>result will be faster contact wear. Another result
>could be failure to break the circuit at all, depending
>on the voltage, or contacts welding together.

---
I missed the part where he said he wanted to run the contact sets in
parallel...

--
John Fields
Professional Circuit Designer
.

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