DPDT Relays needed

Apparently not otherwise they'd have found them at RS.

Care to give the part number of one you consider suitable?

Why? Are you incapable of reading or do you not understand a product datasheet?

RS Stock no. 376-880

But as there are SPST solutions up to 70A that'll fit in a standard automotive 5 terminal relay socket, it seems a bit daft.

Thanks for all the responses. Yes I really do need 30A well ok 25A. It's a common problem with electric windows on 70's Italian cars. You can build a relayed circuit to reduce the length of the ground wire which significantly speeds the motors up.

I couldn't find any cheap DPST or DPDT relays so I doubled up and used 4 SPDT relays from Maplin (£2 each) to replace 2 DPST. It fixed my problem.

I did need 25A to be sure I'd handle the motor current. The motors are fused with a 25A fuse so I figured it would be best to go for that rating.

thanks

Lee

But you don't need a DPDT relay for electric windows - two SPDT are the norm. If you contact me (observe spam trap at bottom of post) I'll mail you a circuit diagram of the common way.

I'd be interested to see details of this ('cause I don't believe it for a minute).

If the relays are in the door (usually luxury cars only, which probably includes any Italian car that had electric wondows in the '70s), then adding a decent earth strap across the hinge is often useful.

You don't need to run a ground to the motors though, because the usual circuit is a reversible motor between two SPDT relays switching each end of the motor from ground to +12V. Close one relay at a time for up or down. If there's no good earth at the relays then you could do with adding one. They'll usually be under the dash though and already have a good earth. I can't see why running an earth near the motors helps though.

Did you get the diagram I sent you in response to your e-mail?

Hi Dave,

Yes thanks, sorry for not replying earlier.

Looks good to me, so I'm going to try it out as I have a bunch of SPDT relays hanging about

Lee