How much current does a gauge draw?

[chimpboy]

Added together, how much current would an ordinary fuel and temp gauge draw? I realise it wouldn't be much but I am wondering how low it is.

[T_Diesel]

I'll take a stab at less than 250mA.

[stuee]

Agree that it will be close to insignificant. Lower than any automotive grade wire that you find in the shops.

Unless they're back lit of course. Whats the context of the question? (ie wiring purposes, curiosity etc)

[chimpboy]

Agree that it will be close to insignificant. Lower than any automotive grade wire that you find in the shops.

Unless they're back lit of course. Whats the context of the question? (ie wiring purposes, curiosity etc)

Partly curiosity, partly that 1970s cars have mechanical voltage regulators to drive the gauges. My stag along with rovers and other junk of the same era has a voltage regulator that supplies a steady 10V to the gauges. It works surprisingly well but obviously there are basic electronic devices to do the same job now.

I was going to replace it with a basic LM317-based circuit board, pre-made like this: http://cgi.ebay.com.au/LM317-DC-In-5-24 ... 0462048735

... which just uses a pair of resistors (one adjustable) to control output voltage.

But then on reflection I thought that it would be even simpler to get a non-adjustable thing like this:

http://www.jaycar.com.au/productView.asp?ID=ZV1509

... as long as there's less than an amp of draw.

So, just a minor little improvement I had in mind. Either way I will measure the current before I start so I'll post the answer first anyhow.

[stuee]

If not there are solutions which would use something like this:
http://www.altronics.com.au/index.asp?a ... m&id=Z0565

That could be used instead. 5A output and the data sheet will give you the necessary circuit diagrams.

edit* thing is that those single output circuits often need some sort of filter circuit put on them anyway (couple of caps) so a couple of resistors isn't going to make a big difference.

Double edit. I gotta stop going to the pub at lunch cause i do no work in the arvo and my posts get stuffed up...

[DamTriton]

If not there are solutions which would use something like this:
http://www.altronics.com.au/index.asp?a ... m&id=Z0565

That could be used instead. 5A output and the data sheet will give you the necessary circuit diagrams.

edit* thing is that those single output circuits often need some sort of filter circuit put on them anyway (couple of caps) so a couple of resistors isn't going to make a big difference.

Double edit. I gotta stop going to the pub at lunch cause i do no work in the arvo and my posts get stuffed up...

Ahhh, POETS day... (Piss Off Early, Tomorrow's Saturday)