w124 Towbar electics

[Hibbo]

That's meant to say "towbar electrics"!

What is the max current I can safely draw from the 12s socket (on pin4 - permanent live)?

Ta!

 

[Ultymate]

It will depend on how it's wired ie. what diameter wire is used and how and where it's connected to on the car. What are you hoping to hook up to it?

 

[television]

If you are thinking on the lines of a bio deisel 5000 gal tanker trailor,you would have to run a special cable direct from the battery.


Malcolm

 

[Hibbo]

It will depend on how it's wired ie. what diameter wire is used and how and where it's connected to on the car. What are you hoping to hook up to it?

If you are thinking on the lines of a bio deisel 5000 gal tanker trailor,you would have to run a special cable direct from the battery.
Malcolm

Not quite, but you're on the right lines.

I'm looking to run a fuel transfer pump from it. The pump has a max current draw of 16A.

 

[Ultymate]

Not quite, but you're on the right lines.

I'm looking to run a fuel transfer pump from it. The pump has a max current draw of 16A.

I would'nt have thought 16amps would cause any problems at all as the permanent live is used for powering up the fridge and van accessories whilst parked up, that said it might pay just to check out how and where it's wired up to, I've seen some really shabby jobs on tow bar wiring over the years

P.S. Electics is a disease common to politicians

 

[Hibbo]

Cheers Ulty,
I'll have a look to see how it's actually wired, but it looks like a very professional job (proper detachable towbar too).

 

[television]

:idea: Why not fit an alternator,belt driven from the trailor wheels,and a self contained battery, it would only need a tiny alternator.:idea:


Malcolm

 

[Ultymate]

An alternative sort of trailer hey Malcolm

 

[Hibbo]

:idea: Why not fit an alternator,belt driven from the trailor wheels,and a self contained battery, it would only need a tiny alternator.:idea:


Malcolm

Because I haven't got a trailer...

 

[television]

Because I haven't got a trailer...

Its all too much for me


Malcolm

 

[Hibbo]

I haven't got a trailer (or any kind of towable contraption) but I do have a 12S plug and the socket is a convenient way to power things!

 

[Hibbo]

It would appear that 16A is indeed to much
Something blew after about 15secs of pumping, hoping and assuming it's the fuse!

What gauge wiring will it need to be for me to fit a 20A fuse (I'm guessing it's a 15A at the mo)?

I've not had a look yet, but are the towbar electrics fuses in the standard fuse box, or will they be elsewhere?

 

[Ultymate]

I would say a 15A fuse would be normal for a fuel pump however if what you're pumping is more viscous than a "normal" fuel it may have pushed up the amps draw of the pump hence popping the fuse the only sure way of finding out what the pumps drawing is to run it direct from a battery with an ammeter in circuit, then fit a fuse in circuit to suit. Wiring wise talking in old imperial which is all my old heads good for I would say 28x.012 should be ok providing the pumps in good order

 

[Hibbo]

Thanks for the quick reply Ulty, the pump is rated at 16A and is a bypass type so I would imagine that its rated 16A draw is when it's dead-headed.

I'll check the wires to the 12S socket and if they look up to it I'll stick a 20A fuse in.