D-type overdrive relay

[Llessur]

Right, complete ignorance here but hopefully someone can help.

Next week sees the big push to finally get the Spit finished and back on the road - with one of the remaining jobs being wiring in of the overdrive. I've got the loom and everything (and *definitely* won't forget about the inhibitor switch) but am missing the relay as I forgot to nab it from the donor car.

I understand that originally a Lucas 6RA type relay was used - which are available from the usual sources for around £20.

I know very little about relays so my questions is - do I specifically need a 6RA type of relay or would different type do the trick? For example one of these from Maplins:

http://www.maplin.co.uk/Module.aspx?ModuleNo=37526

These are much cheaper but maybe there's a reason for this  :-/

Sorry if this is a painfully obvious question but any help much appreciated.

Cheers!

[Richard B]

Just a normal 4-pin relay (Normally Open),  something that will switch 17 amps.

If you want to make it look nice, get one with a mounting plug. Then you wont have to worry about which wire goes where if you remove it.

[Paudman]

Search 6RA on eBay, dozens for sale, cheapest new is 99p, average price for buy-it-now is around £12.
Colin

[Jason]

All the relay does is switch things electrically, so you need one that's capable of handling the current draw required by the solenoid - as Richard says, 17 amps. Any relay that meets the spec will do, Maplins, Radio Spares, any of those places.

[Llessur]

Brill, cheers for the quick responses!

So, from what I understand - the 12v, 30amp version from maplins (link below) should do the trick?

http://www.maplin.co.uk/Module.aspx?ModuleNo=37526

R

[Velocita Rosso]

Maplins?No,no,no,no..................Ive just taken some back to Maplins, either not switching, sounding like arc-ing or sticking on . The guy looked at me and shook his head as if it was my fault .Fitted an old sixties one from out of next doors MGB and had no problems.Prefer the 6RA

[Richard B]

http://www.vehicle-wiring-products.eu/VWP-onlinestore/relays/relays.php
http://www.vehicle-wiring-products.eu/VWP-onlinestore/relays/sockets.php



or

http://www.autoelectricsupplies.co.uk/product/169
http://www.autoelectricsupplies.co.uk/product/701

[Llessur]

Cheers again all - I've just been rummaging around in the shed and have found one that I actually bought for a Fiat Uno a while ago but never used.

It's a 30amp 12v relay but it's got 5 terminals instead of four - they're numbered 30, 85, 86, 87 and 87a.

From what I've read these are for situations when a changeover is required as per the below which I have found on the good old internet:

"In this type of relay connections 30 and 87a are NORMALLY CONNECTED. When the relay is operated (energised) the changeover switch disconnects terminal 87a from terminal 30 and connects terminal 87"

Does this mean I can essentially wire it as per a 4 terminal relay (ignoring terminal 87a) or should I just splash out the whopping £2.50 and get a 4 terminal one?

Bear in mind that I know a place you can get a decent pint for £2.50...  ;)

[bodders1]

Just wire it up like a normal 4-terminal relay and ignore terminal 87a.  Job's a goodun.
Just make sure that you wrap some insulation around the unused terminal to avoid the possibility of inadvertant short-circuit and fire (it will normally be live when the relay is not activated)

[Velocita Rosso]

bodders1 wrote:

Just make sure that you wrap some insulation around the unused terminal to avoid the possibility of inadvertant short-circuit and fire (it will normally be live when the relay is not activated)

OR
Push an unwired,shrouded spade onto the terminal

[bodders1]

michael_charlton wrote:

OR
Push an unwired,shrouded spade onto the terminal

good thinking :-)

[Llessur]

Cheers all! Very helpful indeed.

I'll have a bash next week and let you know how I get on.

Can't wait to get the old girl back on the road now!!!

8)