Electronics Question #4 (Advanced)

[SideKick]

Hi Guys

So hopefully this will be my last question. It's a more complicated one that involves the following parts:

Lets start at a point. The relay.

The numbers on there is, top left 86, top right 87, bottom left 85, bottom right 30 (on the bottom it says 30/51).

OK. 87 goes to the positive on my battery. 85 goes to the engine bay wall (which is negative, isn't it?). 30/51 doesn't go anywhere. 86 goes to that switch I asked about yesterday in question #2 here: viewtopic.php?f=3&t=25572" onclick="window.open(this.href);return false; It goes to the middle "load" pin on the switch.

On that plug is Earth, Load and Supply. Load goes to the relay like I said. Earth goes to the body /earth/negative. And the supply pin gets split into a blue wire and a yellow wire. It goes both to my ignition AND it goes into the back of my CD player. Blue wire to the ignition and yellow wire to my radio. (photo supplied at the top)

The radio's manual says this:

Radio 2.JPG (12.94 KiB) Viewed 2046 times

I've turned that red switch on and off, disconnected it, and I can't figure out what it does . . .

Any of you electrically smart people have any idea That looks like a massive complicated setup that does nothing . . .

[Royco]

My guess is for spots. The blue wire could be to get power when your brights are on.
As for the connection to the radio.... no idea!?!

[SideKick]

Update:

I read through everything again and found this:

Radio 3.JPG (25.19 KiB) Viewed 2040 times

Isn't that yellow wire maybe connected to #3 instead of #4 with the wrong colour wire?

And no matter if that's right or wrong, still, why the insanely complicated wiring?

[ThysdJ]

Seems like a very complicated way of wiring in a switch to kill the power to the radio/cd...

[SideKick]

My guess is for spots. The blue wire could be to get power when your brights are on.
As for the connection to the radio.... no idea!?!

Nope . I can't find any connection between that and my spots . . .

Seems like a very complicated way of wiring in a switch to kill the power to the radio/cd...

Nope . Radio's always working. Turned switch on and off AND took it out completely . . .

[cprinsloo]

Hi Stephan,

The relay was used to supply something, you can use it to energise a Cole-Hersee solenoid for a dual-battery setup, that is if the switch and relay are still working. The earth wire on the switch is to enegise the globe in the switch if it is switched on.

Blue (ignition) wire to the switch and CD player is to switch on the CD when you turn the key. It is not the main supply to the CD, but usually it will only tell the CD that the ignition is on and it will energise. Usually the CD will get constant 12 v supply on the RED wire, that will keep the memory of the CD alive, so that the same song will start to play as when you switched the ign off.

It seems that they split ignition supply (BLUE) to both the switch and to the CD. Reason that the switch is only getting ignition power is that when you switch on the switch, the relay is energised when you switch on the ignition, when you switch the switch off the relay will switch off, but both relay(switch doesn't have power) and CD will be switched off when ignition is off.

Send me your e-mail addres I'll send you a picture (if you want).

1. Ignition supply both switch and CD.
2. Switch supply relay (when switched on).
3. Relay contact supply spots/Cole hersee/etc when both IGN ON and switch ON.
4. If ign OFF then CD and switch have no power (both are OFF).
5 If switch is OFF (or have no power because ignition is OFF), then then relay contacts are OPEN (do not supply power to spots/cole hersee).

Cheers,

C

[SideKick]

OK. I read your post now a couple of times.

So basicly it works like this? If I connect up something to that open point on the relay, then whatever I put on there will also turn on with my radio when I turn the key, BUT I can also use that red switch to turn it off if I don't want it on?

[SideKick]

But why the relay then? Can't you do that without the relay?

[cprinsloo]

But why the relay then? Can't you do that without the relay?

Depends on the load, the relay can carry more current e.g. 2 x 100w spots can draw 8 amps each (16 amp total), you would need a big switch to carry that amount of amps, switches normally can't carry so much, so the switch will burn out, those relays can carry 30 amps.

You can also use that setup to power a fridge while you're driving, as soon as you switch off the power to the fridge will be cut (if you don't have a second battery). Or like I said, if you power a Cole-Hersee to power a second battery, power will be cut when ignition switched off, so that you don't drain the primary battery.

Good luck,

C

[LouisZ]

Looks if there is too much unwanted/unused wiring. Look what needs to be powered ie, spots compressor etc. Take out and rather do a decent new wiring of the items.

[SideKick]

But why the relay then? Can't you do that without the relay?

Depends on the load, the relay can carry more current e.g. 2 x 100w spots can draw 8 amps each (16 amp total), you would need a big switch to carry that amount of amps, switches normally can't carry so much, so the switch will burn out, those relays can carry 30 amps.

You can also use that setup to power a fridge while you're driving, as soon as you switch off the power to the fridge will be cut (if you don't have a second battery). Or like I said, if you power a Cole-Hersee to power a second battery, power will be cut when ignition switched off, so that you don't drain the primary battery.

Good luck,

C

Not sure I understand.

There's already a solenoid installed and connected to the back where the second battery goes.

IMG_0242.JPG (49.58 KiB) Viewed 2003 times

And it's also not connected to these wires in any way . . .

[SideKick]

Looks if there is too much unwanted/unused wiring. Look what needs to be powered ie, spots compressor etc. Take out and rather do a decent new wiring of the items.

That's what I'm trying to do . . . Trying to figure out what's needed and what's not . . .

[cprinsloo]

But why the relay then? Can't you do that without the relay?

Depends on the load, the relay can carry more current e.g. 2 x 100w spots can draw 8 amps each (16 amp total), you would need a big switch to carry that amount of amps, switches normally can't carry so much, so the switch will burn out, those relays can carry 30 amps.

You can also use that setup to power a fridge while you're driving, as soon as you switch off the power to the fridge will be cut (if you don't have a second battery). Or like I said, if you power a Cole-Hersee to power a second battery, power will be cut when ignition switched off, so that you don't drain the primary battery.

Good luck,

C

Not sure I understand.

There's already a solenoid installed and connected to the back where the second battery goes.

IMG_0242.JPG

And it's also not connected to these wires in any way . . .

A solenoid (coil) has something called inductance, the bigger the solenoid, the more inductance (has to do with the number of turns and amps through it), and any coil will have energy while it is energised. When the contact is opened, that enegy will dissipate over the contacts by means of a spark, the bigger the solenoid the bigger the spark, and the spark can "corrode" the contacts over time so that there will not be good current eventually, and the contact will fail because of too high internal resistance etc.

I think you can connect the switch directly to the big solenoid (cut out the small one)....

Cheers,

C

[SideKick]

Nope. I was hanging in there a bit, but now you lost me completely . . .

But the fact is, I can rip that all out, right? Relay, switch, extra wires? And just run wire straight from radio to ignition . . .

Correct?

[cprinsloo]

Nope. I was hanging in there a bit, but now you lost me completely . . .

But the fact is, I can rip that all out, right? Relay, switch, extra wires? And just run wire straight from radio to ignition . . .

Correct?

Do you only want power to the radio/CD? Is yes, then you can rip out everything.

[MOFASA]

If it just your radio you want to power then do it this way....

Main power into radio (normally red) goes to permanent power ie. straight to your battery.....
if you want your radio to turn off when ignition is off then connect the ignition wire from the radio(normally the blue wire) to the ignition wire.....

If you want the radio to run without the key in the car connect the blue and red wire from the radio to permanent power.... This is not the best way to do it cos if you forget the radio on you will drain your battery....