Before I get 10000 responses about searching the forum, or tons of links, I have searched the forum, and looked at all of the links. I have a 3 wire alternator, not going to buy a 1 wire, and an amp guage in my Cameo. No I am not going to run a volt meter because I cant find one as a replacement for this truck, and I don't want one hanging from the underside of the dash. Back to the point. How do I wire this up? Every schematic I have seen shows either a 1 wire install, or an indicator light, again I have neither. I am using a kit from keepitclean, and they leave everything to the imagination! So I know the Batt and red wire go to the battery, how do I hook up the guage? Thanks!
Two splade connectors and a little stud next to them. You would loop a wire off the stud to the tang on the left (as looking from the front) that's your exciter wire then the other tang is what goes back to your fuse box. Run that wire to your amp gauge, then out the other side of the gauge to your fuse box.
Wiring up an ammeter is simple, but the ammeter must be capable of the maximum output of the alternator. If the alternator is 110 ampere output, then the ammeter will need to be that or more. Your ammeter is probably in the range of 30 amperes, which will not do you much good. But there is a work around. If you put a shunt resistor across the ammeter terminals, then the ammeter will only get a portion of the current, while the rest goes through the shunt resistor. If you have an ammeter with a D & C at the extremes, then this will work well. But if you have -30 and +30 at the extremes it may be impossible to match up with 110 ampere alternator. But you can match the 30 amperes readings with the correct shunt resistor. I know this is fairly complicated to most people, but that is the better and safer way to do the amps gauges with alternators. As far as connections: One side of amp gauge goes directly to battery or battery terminal on solenoid. Other side of amp gauge goes to ignition switch, headlight switch, ie: all possible loads, and also the heavy gauge wire from the stud on alternator. That wire should be at least 12 gauge. Terminal #1 should be exciter or field terminal and should be run through a diode to the ignition terminal, or to the ignition switch side of the ballast resistor. Terminal #2 is the sense wire and should have a wire run back to the battery or battery terminal on the solenoid. This wire senses voltage at battery and adjusts voltage regulator for proper charging voltage at battery. (You may want to get a diagram showing the actual terminals on the alternator. This diagram should be in one of the sections of the HAMB)
I think there's a diagram in here if my memory is right http://www.madelectrical.com/electrical-tech.shtml
Thanks for all of the helpfull input! So what I have gathered from the above posts/diagram, is that I am going to run the wire from my fuse box labeled alt up to the amp guage, then the other side out to the alternator. the red wire will loop to the stud, and go back to the battery connection. I am running HEI, so I have no ballast. If this is not correct, what type of diode do I ask/look for, and I have seen several other posts stating the need for a fusable link between the alt and batt...yes or no? Thanks Again!
The amp meter needs to be between all loads and the battery other than the starter. You don't want to know how much the alternator is putting out but how much is getting to the battery
Yes usually you run a heavy red wire from the starter battery post up to the ammeter and then feed the fuse box from the other side of the ammeter. That way the ammeter will show a discharge if something is left on. I always look at the ammeter as I'm getting out to make sure I didn't leave the lights on or have a stuck brake light switch etc.. An ammeter is a flow meter that show which way the amps are going. With everything off it will show no flow. I always use a fusible link in that wire at the starter for protection from shorts. I had an alternator short out inside and without the fusible link it tried to burn the truck down until I yanked on the wire breaking the connection. That won't happen with a fusible link.
Are these the instructions you are using? http://files.thehoffmangroup.com/instructions/kickz.pdf If so I can see why you are having problems. The alternator diagram has the wire color/description labels reversed and I don't see the red/white Alt/starter wire even listed in the engine/front checklist or is it a separate wire? To properly use a ammeter in this kit the B2 wire (8awg, red, Batt) is the one that would go through the ammeter. But please listen to what d2 willys has to say about alternator output and ammeter limits. I've seen (and repaired) wiring meltdowns caused by ammeter issues and it's not pretty. Also if I'm looking at the wrong instructions please post what the item ID number is of the kit you are using and I'll look at those.
Nope, this will only show you how much current the alternator is putting out, it won't show you what you want to know, which is how much current is going into or out of the battery. The battery connects to one side of the ammeter, the other side of the ammeter connects to the rest of the truck (fuse box, alternator, etc). You have to be careful with the wiring of this. The ammeter in these trucks is designed to handle about 30-40 amps max, and if you have a high power alternator and lots of power hungry "devices" in your truck, you might overload the wiring and/or ammeter and melt/burn stuff. Make sure there is a fuse or fusible link in the wire that connects the ammeter to the battery, put it near the battery end. Also the wire from the ammeter does not normally connect directly to the battery, but usually to the battery cable where it connects to the starter. Good luck, this is tricky stuff that you really want to make sure you know what you're doing.
A 1973 service manual show this basic schematic. Interesting that the amp guage is actually a shunt, in other words the electrical load is not carried by the gauge. If your factory gauge is 30 amps this set up might work for you.
Yes make sure that your ampmeter has the same capacity as the out pput of your alternator. All it should actually register is the amperage draw of your components but it should still have the capacity of your alternator. IE 30 amp meter does not go with 65 amp alternator.
Here's one I drew up from the wiring in my early Bronco. Similar to whats already posted. It just shows if the battery is being charged or discharged to let you know if the alt is dead or just can't keep up. It reads 30 amps, but came with a 65 amp alternator. The meter has a sensing loop around the battery to fusebox wire, the current doesn't actually go through the gauge.
Yes, this is what I was going to suggest. But you do have to realize that the wire between the horn relay and the ammeter side going to solenoid is actually a fuse link or resistive wire, which in parallel to the ammeter will allow the ammeter to carry a safe amount of current without damage or starting a fire. You can use a 16 gauge wire for a fusible or resistive link and see where the ammeter reads. An easy way of checking is to turn on the headlights and check the current draw without the engine running. Should read around 10 amperes on the D or - side of the ammeter. It may be possible to put a resistor and diode (resistor and diode are wired in series with ends going to ammeter) in parallel with the ammeter to allow the shunt to be in circuit only with the engine on and charging. This would route some of the current through the shunt. The diode would allow no shunt when engine is off and allow for typical loads to use the ammeter only for actual current readings. Diode direction would have the cathode (or band) wired to battery side of ammeter. The diode approach would not be needed (only the shunt resistor) if you plan on using high current stereos and equipment that draw more than the ammeter can handle.
10g wire from the alternater output to battery has .00118 ohms per ft, that should be enough resistance for the shunt to see as a volt drop, and will show as amps on the dash gage. Be sure to measure the current to your stock ammeter when all wired up, with a DVOM or other reliable meter on the actual 12 guage wires, it should be less than 25 amps under full charge or discharge readings. If not add resister to limit current, you do not want the gage circuit to be the load circuit.
The old SUN ammeter used to have a remote shunt to measure current. That way you still kept the Alt-Bat wire as short as possible. Do they still sell remote shunt set-ups???? It would be a safer, surer way to go.
Gentlemen, it is not my business to give wiring advise, but I need to correct a previous statement. You do not need an ammeter rated for amperage greater than your alternator output. An ammeter monitors the flow of current into or out of your battery. You will rarely have 100 amps going in either direction.
I make & use shunts. The older mopars with ammeters came with 37 amp alternators. Adding a 70 amp alternator is a fire hazard on those cars without a shunt. And yes, a 140 amp alternator can send 100+ amps to the battery after a long cold crank. Make sure the charge path is up to the task. B.
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