Volt or Amp gauge BE A Sport and vote

[pongo]

Trying to decide on which gauge will be better.

Basically trying to keep an eye on the electrical happenings on my old patrol.

Just not real keen on having wire that can handle 60+ amps running in and out of the cab creating a bigger volt drop.

Thanks

[me3@neuralfibre.com]

Does your fuel tank come with
a) A level gauge? (Volts)
b) A flow gauge? (Current)

Exactly

But hey, it's Jap, rice me baby
If it's got the stock patrol alternator about 2A should be enough, that's all it puts out from memory.

Paul

[pongo]

Does your fuel tank come with
a) A level gauge? (Volts)
b) A flow gauge? (Current)

Exactly

But hey, it's Jap, rice me baby
If it's got the stock patrol alternator about 2A should be enough, that's all it puts out from memory.

Paul

well put, Based on that ill get a volt gauge, SO once all 6 gauges turn up, i can mount them all and that should be plenty of Rice. The price you pay to know what your fuel and engine is doing

[drivesafe]

Hi pongo, just fit a volt meter and save a lot of hassles.

You have already hit on part of the problem of fitting a standard amp meter, the additional long run of cable needed will also cause a voltage drop, no matter how thick it is.

You can go for a digital readout type monitoring system but they cost heaps and not sure they are really going to help you all that much.

Just a suggestion, cheers.

[Bluey]

voltmeter, just make it a good one with decent accuracy and resolution. my voltmeter is to 2 decimal places, can't remember accuracy but is very very close to my fluke dmm, and it is self powered (ie powered by the circuit it is measuring).

ammeter are a bugger to wire in, although wiring a shunt in the engine bay and then measuring the voltage across it will give the current, plus smaller wires to the dash. reasonably easy to. anyway, resolution could be a big problem if you have big accessories eg a winch

[da60]

Well, having a volt meter will give you a rough estimation of how the alternator is performing. ie( reading closer to 12 flat says you are getting near your alternator output). But having a amp meter will tell you definately if your pull more current than your alternator can provide.

[Bluey]

only if absolutely everything goes through the ammeter. this is easier when you only have one battery or they are at least mounted near each other. ideal setup is both, if one only get a voltmeter

[me3@neuralfibre.com]

FYI Jaycar sell a nice LCD one for about $30 that has a clock with it and backlit. Don't go the combo temp one, it has batteries and other issues.

Paul

[j-top paj]

id go the voltmeter

[chimpboy]

I would love an ammeter but it's not realistically easy or cost effective to install, so voltmeter it is.

[cruiser60series]

my troopy has a stock ammeter ... but it doesn't work. Will be chucking in a voltmeter soon and that tells you enough.

[HotFourOk]

I had the same dilemma a few months back.... bought the Pirahna dual battery voltmeter and couldn't be happier!

You know if you're drawing too much via the battery voltage anyways.. and you can check on the condition of them also.

[Shadow]

Whats so hard or expensive about using an ammetre?

Use a shunt resistor and any volt meter and you have an ammeter.

I dont think anyone with any idea of electronics would run the main battery cable into the cab, through a panel meter, and then back into the engine bay. Thats just really dumb.


Practicality thugh, a voltmeter is probably more useful.

[-Scott-]

Whats so hard or expensive about using an ammetre?

Use a shunt resistor and any volt meter and you have an ammeter.

I dont think anyone with any idea of electronics would run the main battery cable into the cab, through a panel meter, and then back into the engine bay. Thats just really dumb.

Well...

Yes, I admit, I did it to my first car - about 18 years ago. I only shorted the cable once.

I reckon you don't even need a known shunt. WGAF precisely what amps are flowing? Primarily, I'm interested in whether it's charging or discharging, and if it's a lot, or a little. Precise calibration?

A simple non-linear amplifier driving a centre-zero voltmeter, reading voltage over any suitable length of battery cable (effectively, an uncalibrated shunt) should be adequate. High gain to read low current, with gain dropping off as shunt voltage rises so you can display higher currents.

I'm just too lazy to figure it out.

[rainsey]

I would love an ammeter but it's not realistically easy or cost effective to install, so voltmeter it is.

Folks,

Any one with a little bit of soldering capability can build a very cheap ammeter that does not require shunts, of the risk of big cables shorting out. Altronics sell an 80Amp digital ammeter kit that uses a Hall effect device.
http://www.altronics.com.au/index.asp?a ... m&id=K4336
It is basically a clamp ammeter. A ferite core clamps over the +ve cable off the battery, the magnetic field generated in the battery cable in turn creates a current at the hall effect device that is proportional to the current. Safe, easy and cheap. I have 2 in my truck, one on each battery.

Cheers

Rainsey

[-Scott-]

I would love an ammeter but it's not realistically easy or cost effective to install, so voltmeter it is.

Folks,

Any one with a little bit of soldering capability can build a very cheap ammeter that does not require shunts, of the risk of big cables shorting out. Altronics sell an 80Amp digital ammeter kit that uses a Hall effect device.
http://www.altronics.com.au/index.asp?a ... m&id=K4336
It is basically a clamp ammeter. A ferite core clamps over the +ve cable off the battery, the magnetic field generated in the battery cable in turn creates a current at the hall effect device that is proportional to the current. Safe, easy and cheap. I have 2 in my truck, one on each battery.

Cheers

Rainsey

Yes, they're a good solution, but (last time I read up on them) you need to stay within the limits of the Hall effect device - go too high and it develops a "memory" (for want of a better word) and gives a wrong reading.