Electrical Relay

[rpgdeity]

I'll be putting some Bosch type 5 pin relays in my 715 soon to power aux. lights and the such. Can someone please verify the pin wiring? I think its supposed to be like this:

87a - is the normally open terminal, this goes to the item your turning on
87 - not used
86 - to your 12v switch
85 - to ground
30 - to a 12v constant source

Is this correct? Thank you.

[Barrman]

You do realize that there are like 121 different ways a relay could be wired internally, right?

Look at the side of the relay and it should show a schematic of it. Your numbers sound like the right wires in the right way for some relays. Seriously, look for the schematic or make one yourself. I have to do that when messing with them to keep it straight in my head.

[FSJGuy]

The one's @ Radio Shack and AutoZone have a similar numbering system. Compare them with the schematic and you should be able to figure it out.

[brute4c]

I have this from JP magazine:




Notice the upper pic is detailing the 85 and 86 side of things....the low voltage side of the magnetic connection, and the lower part shows the high voltage side of things.

The magnetic connection is internal in the relay.

So one of the 87 wires, your choice, will turn the device in question on and the other will turn it off. Looks like both need to hook to the device to be controlled but they cant be hooked to each other...not sure how one does that in all situations....like at a headlight for example...

[brute4c]

Note: this is for a Bosch 5 pin relay.

[rpgdeity]

Barrman, No, I was not aware that there is a myriad of different relays available. I've only seen the automotive type, and they all seem to have close to the same numbering system, so I thought that maybe there was a standard of some type.

I'm looking at the schematic right now, and it doesn't make much sense to me. There are a couple different variations in schematics between different relays that I see, and I'm just confused as to which type I need for my application. I will consult my local Radios Shack, as they are pretty good with helping pick out the right type of stuff.

EDIT: Thanks Brute4c, thats what I was looking for.

[Barrman]

That is the point. There will be a number on the top of the relay. Most cars have about 4 or 5 different number relays doing different stuff. They will all plug into the same plug though.

Some are power on, some are power off, some are extended time and some are for brief use.

I wasn't trying to write like a smart alek. I was just looking for which exact relay you have. That is the only way to tell you an exact answer.

[rpgdeity]

No, your good Barrman, I knew your weren't trying to be smart. I was actually hoping you would post up, as I knew you would be able to give me some good info. Knowing that there are many different configurations, versus some kind of standard is an equally important piece of info that I did not know.

Looking at the schematic from Brute4c makes much more sense than the schematic I'm looking at in this catalog of 5 pin Bosch relays. I now understand how you can have a normally open, or normally closed relay from the same type of relay. This is the difference between the "87" and "87a" terminal. I was confused about that before.

[Barrman]

Just to add to your confusion you also have some that power two different circuits depending on if the relay is hot or not.

I used one of those types for my reverse lights on the 715. When the relay is off, the lights come on with a switch. When the relay is hot, the lights come on with the reverse switch in the transmission.

[osut362]

if you havent bought the relays yet, well.... keep it simple. i've used 60's ford and chrysler realys. only three pins, one for switch, one for battery feed, and one to the load, i grounds to the mounting screw....ain't no plastic parts in my 715 so ground is not a problem