From: "Tom Faloon"
Subject: Re: Help with relays please.
Date: Thu, 26 Sep 2002 19:48:44 +0100
NNTP-Posting-Date: Thu, 26 Sep 2002 18:45:48 +0000 (UTC)
X-Newsreader: Microsoft Outlook Express 5.00.2615.200
You could of course replace the relay by a solid state design, but only go
there if you want the technical challenge, and you don't mind the
If you just want your vehicle to work reliably, then find out why the relays
are failing and fix the problem.
What is actually wrong with the failed relays?
(Are the contacts burning out, or is it some other type of failure)
Is this a known problem with your vehicle model.
Are you fitting relays specified by the manufacturer?
(Or a cheap alternative?)
Are you running the winch more often than average?
If you want the challenge, you may be able to source a solid state relay,
otherwise I would suggest MOSFET's,
but you will need several in parallel. You will need effective heatsinking
and over voltage and current overload protection, otherwise the solid state
solution may be more fragile than what you have already. Then there are the
400Amp connections, and making it all fit in the space available. This is
not a two hour project, but you could have satisfaction at the end of it!
Martin Perry wrote in message
> I have a truck winch that is controlled by a number of relays. The
> relays fail after a short period of time. There is nothing wrong with
> the winch motor. The 12 volt relays switch 12 volts at a peak current
> of about 400 amps. Would it be possible to replace each relay with a
> triac and a simple circuit? Any help would be appreciated.
> Thanks, Martin Perry