Thread: Using relays for a latching circuit

Originally Posted by BradC

It would. If you search hard enough you might even find one less than 6” in diameter and worth less than the car. A PWM motor controller will be smaller, much cheaper and more reliable.

I'm curious as to why it'd have to be so big?

I was under the impression that a seat heater element is about 5 or 10w max. IIRC I've seen 3w element kits.

I think back when I worked for truck companies, they want 4am starts and Melb winters/autumns/springs can get a bit frosty, and D1 heater took some time to heat themselves up. So I sold the D1 ...

Nah, I looked into fitting heated elements after I replaced seat spring and foams on the drivers side and was quite easy to do in the end, so had me thinking.
... and thinking and thinking .....

Years later did nothing, sold D1 and moved to a colder region in autumn/winter/spring!... much hotter in summer tho.

But back then with my expectation that the element is about 5w or so, I thought that using a 15w pot would suffice(easily available at Jaycar). It's only 40mm in diameter, and less than $20.

Any reason why you wouldn't use something like that?
I'm definitely no electrical expert, I just thought that as long as the pots capacity is greater than the element capacity, it would be durable.

Haven't had a look at your circuit in detail, but I wonder if this would help.