Ammeter
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From: Comox Valley, Canada
Ammeter
Most ammeters require an external shunt. This prevents nearly instantaneous ammeter failure the first time you power up the truck accompanied by all the smoke leaking out of the ammeter 
and we all know that when all the smoke leaks out of an electrical device it seldom continues to function. Which goes along way to prove my theroy that electricity is actually in the form of smoke
The shunt is in series with the main power wire and the ammeter is in parallel with the shunt. Meaning... power wire from alternator to one end of shunt, power feed wire from the other end of the shunt to the start relay/battery positve connection (usually), 1 ammeter connection to one end of shunt and another to the other end of the shunt.
Sparky
and we all know that when all the smoke leaks out of an electrical device it seldom continues to function. Which goes along way to prove my theroy that electricity is actually in the form of smoke The shunt is in series with the main power wire and the ammeter is in parallel with the shunt. Meaning... power wire from alternator to one end of shunt, power feed wire from the other end of the shunt to the start relay/battery positve connection (usually), 1 ammeter connection to one end of shunt and another to the other end of the shunt.
Sparky
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Joined: Sep 2001
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Ammeter
Thanks Sparky!
I agree with your smoke assesment. It seems to be true for most electrical devices.
Are you familiar with the newer solid state devices like LED's?
LED==Light emitting diode
DED==Darkness emitting diode
SED==Smoke emitting diode
FED==Flame emitting diode
PED==Particle or Plasma emitting diode
Electricity can appear in other forms too...:-)
I agree with your smoke assesment. It seems to be true for most electrical devices.
Are you familiar with the newer solid state devices like LED's?
LED==Light emitting diode
DED==Darkness emitting diode
SED==Smoke emitting diode
FED==Flame emitting diode
PED==Particle or Plasma emitting diode
Electricity can appear in other forms too...:-)
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From: clementsport canada
Ammeter
i'm i reading this wrong, or do you mean, leave the power wire from the alt. to the batt. terminal of the solinoid, and connect a wire from the alt power to the ampmeter, then from the ampmeter to the batt terminal, thus having 2 charge wires? i can see how this would save the ampmeter, but does it still read correctly? pardon me if i'm wrong.. it's been a long day...
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Joined: Apr 2001
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From: texarkana, tx
Ammeter
Hey Sparky --- true, there IS smoke in them thar wires!! I stuck a screwdriver down there in my computer one day while it was on. Hey!....looked like the 4th of Jooly and I had a LOT of smoke too!!
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Joined: Jan 2001
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Ammeter
It sounds to me like you are connecting the meter from power to ground. This will cause a direct short to ground, max current flow and a well toasted ammeter.
With regards to the shunt. The factory meter has one. I've never seen one to be used with an aftermarket meter and I've never seen it mentioned in the installation instructions. Even my hand-held Fluke doesn't use an external shunt. The shunt is internal to these meters. The instructions to the aftermarket meters state to splice it into the circuit.
To THEONLYBULL, what you describe is the correct way to connect the ammeter. My concern is, and I'll have to check my truck, that I think the main lead to the fuse box connects to the batt terminal of the start solenoid. If this is the case then once the battery is charged, the ammeter will read zero amps and any drain on the battery will not go through the meter (ie headlights left on etc). I would try to connect the fuse box on the alterntator side of the ammeter so any discharge out of the battery has to go through the meter.
With regards to the shunt. The factory meter has one. I've never seen one to be used with an aftermarket meter and I've never seen it mentioned in the installation instructions. Even my hand-held Fluke doesn't use an external shunt. The shunt is internal to these meters. The instructions to the aftermarket meters state to splice it into the circuit.
To THEONLYBULL, what you describe is the correct way to connect the ammeter. My concern is, and I'll have to check my truck, that I think the main lead to the fuse box connects to the batt terminal of the start solenoid. If this is the case then once the battery is charged, the ammeter will read zero amps and any drain on the battery will not go through the meter (ie headlights left on etc). I would try to connect the fuse box on the alterntator side of the ammeter so any discharge out of the battery has to go through the meter.
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From: clementsport canada
Ammeter
76crewcab, thanks for the reply. good point about the fuse panel.. i miss having a ammeter in my truck, since the last one shorted out internally ( causing me alot of headache's b4 i found it)
maybe on the next one i rig up, i'll wire that way..
maybe on the next one i rig up, i'll wire that way..
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Joined: Sep 2002
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From: Mpls US
Ammeter
Yeah,thanks its' the aftermarket ammeter, diagram shows lead from fusebox to neg side of meter, pos side of meter to starter pos and I can smell the coffee brewin'--gettin' a lot of silly guy responses about this, is this normal? Also somebody says something about a shunt across the terminals?? Doesn't seem like that would work unless maybe the ammeter has 0 resistance, which I doubt. Is that a shunt a shunt or a resistor? And then it wouldn't read accurate on amps, maybe just a cheapo ammeter? 
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From: Central Kali
Ammeter
I have a shunt that is good for 50 amps. It consists of two brass blocks with a thin 1 1/4 by 7/8 piece of brass connecting the two blocks. The current to be measured is connected to the two blocks. Also on the blocks are terminals for a voltmeter. If 50 amps is flowing thru the shunt, .05 or 50 millivolts will be produced across the two blocks. The thin piece of brass is a precision resistor. What is it's resistence? .05 volts divided by 50 amps equals .001 ohm. It is calibrated at the factory by drilling a hole in the thin piece until .05 volts is obtained. 
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From: Louisville,Ky.
Ammeter
An after market ampmeter is easy to install. First, you remove all of the leads off of the battery side of the starer solenoid except for the battery cable. Put the eyelets on a bolt along with a wire running to one side of the ampmeter. Then put the battery cable and the wire coming from the other side of the ampmeter on the starter solenoid. Make sure that the bolted together wires are not touching any metal, then turn on the headlights and make sure that the meter goes to the neg side. (If not, reverse the wires on the gauge). Then thoroughly tape up the bolted up wires and it will work fine. I have done this on several vehicles and have never had a problem.
NOTE This applies to aftermarket guages only. Do Not try this on the factory gauge, it only reads a percentage and does not have full current running thru it.
Jimmy
NOTE This applies to aftermarket guages only. Do Not try this on the factory gauge, it only reads a percentage and does not have full current running thru it.
Jimmy