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Ammeter

S

smokejmp52

New User
Converted 1950 8n to 12v , runs like Champ....except the ammeter
isn?t moving from -15. No movement no matter the rpms . When I flip
wires around on terminal block and ammeter, when I started tractor it
pegs to -60 then goes back to -30 . It?s a one sure alternator . Self
igniting . Any ideas why it?s not reading as charging ????
 
When you converted did you happen to change polarity (most alternators use NEG ground) ?? If polarity was reversed you need to swap the ammeter leads or else it would read backwards. If its wired right with tractor off and you turned on lights or ignition the ammeter should swing over to - discharge.

John T
 
Nope not exactly its been too long lol. It has to do with the direction of current flow (how ammeter is wired) affecting the North South magnetic field polarity but you have to talk with a more current and practicing engineer or electrical tech to answer your good question.

Take care and best wishes, sorry I couldn't answer your question

John T
 
Don't know about yours.>>but I remember my father, now that you mention Ford 8N or 9N<< that the amp gage was not directly wired in but USED a COIL rapped around the lead from the generator to the batter/ lights/ switch area of the power circuit. As I say don't know if yours is similar or has been altered by some one before you, but this may be a place to look to see if this is why the amp meter is acting like it is. >>>just a remembering of what my father said <<<
Wm.
 
(quoted from post at 00:10:30 11/01/19) Converted 1950 8n to 12v , runs like Champ....except the ammeter
isn?t moving from -15. No movement no matter the rpms . When I flip
wires around on terminal block and ammeter, when I started tractor it
pegs to -60 then goes back to -30 . It?s a one sure alternator . Self
igniting . Any ideas why it?s not reading as charging ????
Click to expand...
oop style ammeters deflection depend on which direction current is flowing in the wire passing thru the loop. To reverse deflection, pass it'd thruloop in opposite direction, L to R or R to L.
On similar note, if you followed wiring instructions with alt conversion kit, meter likely will never read correctly, because those ferriners seem to be unaware of Net ammeter connections.
 
When you installed the alternator, where did you connect the output wire?

If you connected the wire directly to the battery, then the charge is not being read on the amp meter.

Only if you connected the alternator to the "BAT" wire that was on the regulator, or ran a new wire to the amp meter will it read properly.

When wiring an ampmeter, one side is powered directly from the battery, nothing else on that terminal. The other side connects to the alternator, ign, acceassories, everything else.

Sounds like there may be a problem with the ampmeter. Pegging at 60 and running at 30 can't be right.

Review the wiring, consider replacing the amp meter. Or better yet, replace it with a volt meter wired to the ignition side of the ignition switch.
Ampmeter Wiring
 
Teddy, it responds to the direction the current flows, either from the alternator/generator into the battery (good thing), or from the battery to the electrical load (bad thing).

It's done with a electromagnet coil swinging the needle depending on direction the current is flowing.

As far as knowing which way to wire it, I don't know of any industry wide standard. Often the terminals are not marked. Trial and error, if it reads backward, reverse them.
 
So as it is wired now , direct wire from single connection alternator to right side of ammeter, wire from left side to ammeter to terminal block, everything else wired to terminal block so ignition key must be on. so basically there is a jumper from left side ammeter to terminal block. If I switch the wire from the terminal block that runs from solenoid to right side ammeter and put wire that runs direct from alternator to the terminal block that's when the ammeter goes directly to -60 when starting then goes to around -20 and stays there . So one way says not charging and one way doesn't do anything?
 
(quoted from post at 11:03:48 11/03/19) So as it is wired now , direct wire from single connection alternator to right side of ammeter, wire from left side to ammeter to terminal block, everything else wired to terminal block so ignition key must be on. so basically there is a jumper from left side ammeter to terminal block. If I switch the wire from the terminal block that runs from solenoid to right side ammeter and put wire that runs direct from alternator to the terminal block that's when the ammeter goes directly to -60 when starting then goes to around -20 and stays there . So one way says not charging and one way doesn't do anything?
Click to expand...
y your words, the final connections leave you with NOTHING connected to ammeter left terminal. Therefore it should not be able to read anything. :roll:
 
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