Omega Owners Forum

Omega Help Area => Omega Electrical and Audio Help => Topic started by: twiglet on 18 April 2012, 15:49:31

Title: Suitable relays
Post by: twiglet on 18 April 2012, 15:49:31

I've got some auxillary electrical that I want to install in my work hack, and I want to install them using switches and relays, so I guess I just need the basic 4 pin relays (+12v, earth, switch and load)?

I also have a bucket full of relays that I have removed from several Omegas, and I'm thinking that some of them must be ideal for this application?

Can anyone tell me which Omega relays would would in this scenario?  (Rob, pics would be useful!  ;) )

TIA  :y

Title: Re: Suitable relays
Post by: Andy B on 18 April 2012, 16:03:36

You n
just need something like this ............. http://www.ebay.co.uk/itm/12V-RELAY-4-PIN-AUTOMOTIVE-30AMP-RY1-CHANGEOVER-12-volt-Car-Van-Boat-Spotlight-/280756476397?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item415e63d9ed#ht_2663wt_1139
It might even have a 87a contact on it ie two out outs from the 30 terminal input.
(http://i.ebayimg.com/06/!CDYg0kwBGk~$(KGrHqIOKj4E0tlsWurHBNOY2D(P3!~~_12.JPG)

Title: Re: Suitable relays
Post by: Andy B on 18 April 2012, 16:05:11

depending on the load you intend putting on it, the small rectangular relaysat the top of the relay/fuse box under the column are the same electrically.  :y :y

Title: Re: Suitable relays
Post by: twiglet on 18 April 2012, 16:10:08

Cheers Andy, I knew you'd come to my rescue!  ;D

So if I want to run 2 low current draw outputs from one switch, the correct way to do it would be to connect them to pins 87 and 87a?

Any chance you could confirm the number codes for the other connections, just so I can be absolutely sure I've got it right?

Cheers  :y

Title: Re: Suitable relays
Post by: Andy B on 18 April 2012, 16:36:32

Quote from: twiglet on 18 April 2012, 16:10:08

Cheers Andy, I knew you'd come to my rescue!  ;D

So if I want to run 2 low current draw outputs from one switch, the correct way to do it would be to connect them to pins 87 and 87a?

Any chance you could confirm the number codes for the other connections, just so I can be absolutely sure I've got it right?

Cheers  :y

(http://www.extremeautoaccessories.co.uk/pics/1295617248.jpg)

Not quite. Your load goes across 30 & 87/87a (ie power to 30 & your lamp/etc to 87 &/or 87a) and your switch puts powers across 85 & 85 (ie power from the switch to one & earth the other)

Title: Re: Suitable relays
Post by: twiglet on 19 April 2012, 13:50:33

Cheers Andy, I shall have a play!  :y

Title: Re: Suitable relays
Post by: I_want_an_Omega on 21 April 2012, 22:14:34

Depending on how you are going to be switching these on/off, it might be worth putting a diode across the coil to soak up any back emf nasties generated by the coil when switched off. Think ignition coil in minature.

The diode should be wired right next to the relay coil and connected with the Cathode to the positive and Anode to negative of the coil. This might seem the wrong way round - but the voltage generated by the coil at switchoff is negative - hence connecting the diode this was round.

The 1N4xxx range should do nicely, with the 1N4005 being rated @ 1,000 volts (IIRC) and being quite cheap from Maplins or the like.

It will work without, but is good design practice to use them.

HTH