Electric Window protection

[yung-gun]

Hi guys. trying to wire the electric window into my car and having no joy. seen a couple of wiring diagrams. am i going to need the circuit breaker or can i just put an inline fuse in?

Cheers

[greg124]

I've never known the circuit breaker pop out, so it's unlikely that you would have to change a fuse very often unless you where in the habit of putting something in the way while closing a window.

Come to think of it, I may have a spare circuit breaker kicking about somewhere.

[yung-gun]

so i don't need the breaker, just an in line fuse will do the trick?

[Brianmoooore]

YOU NEED THE BREAKER! The locked rotor current of a window motor is insufficient to blow the fuse.
Several years ago I had an E30 in the workshop that had been converted from manual windows to electric. Whoever had done it had not included the cutout, and had wired them from a permanently live 30A fuse.
I had been doing something in the passenger footwell, when the time came to finish work for the night, and had been absent mindedly placing tools etc. on the centre console. Unknown to me, I had placed a lump hammer on the 'up' button of the driver's window and had shut up the workshop with the button pushed down.
When I came back in the morning, the whole workshop was full of an acrid burning smell, the car's electrics were dead, the window motor was burnt out, as was the window loom, with damage to other wires that it passed near. The 30A fuse was intact.

[yung-gun]

i heard a 15 amp fuse is better.

anyone got a loom for leccu windows?

[fixedwheelnut]

A 15 amp fuse could blow to often with the current spike as the motor starts up, the cut out is there for a reason, I think it uses a Bi-mettallic strip to trip it so the current spike does not heat it up quick enough to trip but if a constant excess current occurs as in Brian's situation the thermal bi mettallic strip would heat up and trip before the loom went up.

Wiring diagram downloads here http://shark.armchair.mb.ca/~dave/BMW/e30/

[Brianmoooore]

There is no limit switch on E30 electric windows. When they reach the end of their travel the motor simply stalls, and the current flowing rockets until you release the switch.
This stall current is sufficient to heat the wire in a 15A fuse considerably, and in time will either fatigue the fuse element and/or cause damage to the fuse holder.
The 30A fuse and the cut out do entirely separate things, and are both required.

[greg124]

I've got the looms that go inside the doors for electric windows, electric mirrors & central locking.
Do you need just fronts, or front and rear?

In light of Mr. Mooooore's comments I'll also have a root around and see if I can find the breaker.

[yung-gun]

The breaker is what i'm after guys, i'll do what ever i can to avoid an electrical fire :p pm me with prices please guys. also may need another electric window switch

[yung-gun]

Still after a electic window contol unit. anyone got one they fancy spelling

[greg124]

Found the cut-out today, if you still need that.

I can't spell control unit though...

[yung-gun]

How much posted to ll19 mate?

[greg124]

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