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Aquarian51
11th July 2011, 11:58 AM
Hi guys. I'm fitting an ammeter guage. The instructions with guage said to connect one wire to the large starter solenoid connection and the other wire to the wire from the small starter solenoid connection and insulate them. I did that, but then the starter won't work as there is no connection to activate it.

A guy from work said to remove the insulation and put the two connected wires back onto the small terminal on the starter solenoid. I tried that, but when I reconnected the battery the starter continuously cranked as I had effectively hotwired it.

Any ideas on how to get this guage to work, please?

YNOT
11th July 2011, 12:18 PM
Big Fletch is probably the right person to answer this but I'll have a go anyway and he can correct me if he needs to.
There are 2 sorts of amp meters, one uses a shunt that fits around the main battery cable and measure the magnetic field around the cable to calculate the current drawer, the other (which it sounds like you have) fits in series with the battery cable and becomes part of the circuit. Effectively you take off the battery cable and put the gauge between the battery and the cable so it becomes part of the circuit.
Wait for Fletch to answer in case I got it wrong.

Tony

patch697
11th July 2011, 12:19 PM
Hi guys. I'm fitting an ammeter guage. The instructions with guage said to connect one wire to the large starter solenoid connection and the other wire to the wire from the small starter solenoid connection and insulate them. I did that, but then the starter won't work as there is no connection to activate it.

A guy from work said to remove the insulation and put the two connected wires back onto the small terminal on the starter solenoid. I tried that, but when I reconnected the battery the starter continuously cranked as I had effectively hotwired it.

Any ideas on how to get this guage to work, please?

in your instructions they are referring (very unclear in its description though) To an older style arraignment where the main power supply wire that powers the hole cars electrical system (the HOT wire) was linked to the battery via the positive battery cable at the starter. This is not the case with a patrol however, & the wire you thought they were referring to is the starter wire hence the result you ended up with but don't stress its a common mistake.

I don't recommend the use of amp gauges because they have been known to cause electrical fires but if you wish to have it then removing your alternator charge wire & placing one of the 2 gauge wires in its place & connecting the other gauge wire to the charge wire you removed (please insulate well & preferably not with electrical tape... Use shrink & apply several layers) will give you an accurate reading...


WARNING As said I do not recommend the use of this gauge if you wish to install one than you do so at your own risk.

the evil twin
11th July 2011, 12:56 PM
What Patch said X 2.

Indeed I didn't think they did those style anymore but possibly meant to be for Stationary Engine Applications. Almost a necessity in older vehicles and Generator based systems they are a rarity these days.

Ammeters were the best way to monitor what was happening in an electrical system but 'shunts' pretty much cause more issues than they are worth incl on rare occasions elec fires so you don't see them used very much anymore. Inductive clamp meters are OK but not very accurate on low current applications relatively speaking.

Like Patch I also would forego an Ammeter in a modern vehicle with an alternator

big_fletch
11th July 2011, 02:06 PM
X3 I also don't recommend wiring in ammeters, I have seen to many failures (burnt wiring, fires ect).. The only thing they are really used on now are some boats, old tractors and as evil said stationary motors.. Tony and Patch have the right idea with the wiring side of things, connecting the ammeter in series with the alt wiring.. I would consider very closely all other options before fitting one..
If your wanting to see what the alt is doing, maybe consider fitting a volt gauge? A lot safer and easy to tell if you have an alt fault as the gauge should be between 13.2-14.4v when engine is running. Anything over or under will indicate a possible fault

Fletcha

Yendor
11th July 2011, 02:07 PM
I with them.

I would not use an ammeter, a good quality volt meter would be the way to go.

Yendor
11th July 2011, 02:11 PM
lol...great minds hey Fletch :thumbup:

big_fletch
11th July 2011, 02:50 PM
lol...great minds hey Fletch :thumbup:

Haha to right mate, thats how we roll lol

fixer982
11th July 2011, 04:30 PM
As everyone said, a series ammeter can cause a lot of trouble. I was once in a car when the ammeter wiring fitted by a mate shorted to the chassis and the car filled with smoke really quickly at 100km/h. As Big Fletch said, fit a voltmeter and this will tell you what you need to know.

Ben-e-boy
11th July 2011, 05:36 PM
I would use an ammeter on my auxillary circuits ie fridge, camp lights etc this will give you a clear idea of when your battery is going flat.
for example if you have a 90 amp/hour battery (battery will be flat in 1 hour if drawing 90 amps) and your ammeter shows 9 amps your battery should last 10 hours. IMO that would be a better use for an ammeter in your patrol, and get it done by a professional. noting bugs me more than backyard electrics

Big Fletch am I safe in saying that you have Redone your fair share of someones dodgy electrics in your time.

big_fletch
11th July 2011, 07:41 PM
I would use an ammeter on my auxillary circuits ie fridge, camp lights etc this will give you a clear idea of when your battery is going flat.
for example if you have a 90 amp/hour battery (battery will be flat in 1 hour if drawing 90 amps) and your ammeter shows 9 amps your battery should last 10 hours. IMO that would be a better use for an ammeter in your patrol, and get it done by a professional. noting bugs me more than backyard electrics

Big Fletch am I safe in saying that you have Redone your fair share of someones dodgy electrics in your time.


I would use an ammeter on my auxillary circuits ie fridge, camp lights etc this will give you a clear idea of when your battery is going flat.
for example if you have a 90 amp/hour battery (battery will be flat in 1 hour if drawing 90 amps) and your ammeter shows 9 amps your battery should last 10 hours. IMO that would be a better use for an ammeter in your patrol, and get it done by a professional. noting bugs me more than backyard electrics

Big Fletch am I safe in saying that you have Redone your fair share of someones dodgy electrics in your time.

I agree that an ammeter can be used in this way if wired correctly and all fused, with fridge or camp lights ect, as this is not a very high current draw application (all up maybe 30 amps). I do a lot of work on orchard machinery (tractors, cherry pickers, old farm trucks), wiring brand new trucks, stationary motors and normal cars and 4wds.. There is nothing worse than dodgy, unfused backyard wiring.. I see a lot of people using 240v 3phase household wiring in there vehicles which is also not the correct cable for 12-24v application.. A lot of old machines use ammeters and we actually completely remove them as they always end up causing problems with burning wires..

Some people will have a different opinions and ways of doing wiring on their own cars, and I'm not saying they are all doing It wrong and don't have a crack yourself at it. I'm saying If your not 100% sure on what your wiring even just drop in for advice from your local Auto-Elec who can steer you in the right direction.
I'm not a fan of ammeters at all in my honest opinion, but if Aquarium51 realli would like one I advise that it is fitted by a qualified Auto-Electrician and fully fused as you said Ben-e-boy.. I Also think it would be better inside the vehicle to keep the dust and water out of it as will definitely cause problems if exposed to the elements for an extended period

Aquarian51
11th July 2011, 08:06 PM
Thanks big_fletch, ET and all other posters. I have already fitted a voltmeter. After my Alternator karked on my Pilbara trip last year and the battery finally died in the middle of nowhere I figured I'd fit the ammeter to keep a good eye on things. I'll try and get a refund for the guage.

Thanks again guys, cheers. Len