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Coley909

Charging at 20 volts!?!?

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So my generator and regulator got rebuilt and today I reinstalled them.

Before I coulis only charge at 12 volts or 20 so I took it in thinking it's the regulator it was both the regulator and armurture failed in the generator.

Anyway back to today I put everything together start it up and I'm at 26+ volts at times but settled back down at 19-20 volts even at low idle. So the guy who rebuilt it knows a ton about this stuff so it makes me wonder is it supposed to charge that high?

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Are you measuring that voltage across the battery? It should be around 13.5-14 volts. 20 volts will fry a battery in no time.

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I would measure at the battery. 

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12.6 at the battery

 

I could live with that, a little on the low side but should increase with throttle. Looks like you're good to go.

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I did only go 3/4 or so throttle so potential for more. I wasn't hanging out outside its 5 degrees at the moment and I just finished putting it all together out there haha

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I would like to see over 13 at 3/4 throttle.  When you get a minute see what it reads with the tractor not running key off, at idle, and full throttle.  I'm wondering if it increases at all.  Just trying to make sure you're ok.  :)

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I gotcha ill check it later when it gets a tad warmer out. I may need a little adjustment on the regulator

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I would like to see over 13 at 3/4 throttle.  When you get a minute see what it reads with the tractor not running key off, at idle, and full throttle.  I'm wondering if it increases at all.  Just trying to make sure you're ok.  

 

:text-yeahthat:

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Is there a good way to adjust the regulator? The last one didn't have an adjustment screw not sure if this one will

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If 20 volts is reaching the battery, the SG is not being controlled by the regulator. Remove the wire from the FIELD (F) terminal of the SG, start the engine and run it at 3/4 throttle again. If the battery voltage remains at 12.x and does not jump to 20, the regulator is at fault. Simply put, the SG is BEING TOLD to produce full voltage by the faulty regulator.

 

Inside the regulator is a relay that only functions to ground or lift the ground from the FIELD terminal. When the field is grounded, the SG puts out full voltage (20 volts you measured earlier). It is the function of the voltage relay in the regulator to un-ground the FIELD terminal when the voltage from the SG reached 14.x

 

If the relay never lifts the ground off the FIELD terminal, the SG puts out full voltage (20 volts).  Since the DC voltage output of the SG is RPM dependent, a slower engine speed results in less SG voltage output. If the regulator is bad (or maladjusted) the SG will only output 12.x volts at idle.

 

This could explain the 12 / 20 volt swing you see at different engine speeds.

 

The good news is it sounds like your SG is healthy.

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12.6 at the battery

 

We have already determined 20V is not reaching the battery.   :)

 

I would like to see over 13 at 3/4 throttle.  When you get a minute see what it reads with the tractor not running key off, at idle, and full throttle.  I'm wondering if it increases at all.  Just trying to make sure you're ok.  :)

 

After we get these results we'll have a better idea of what's going on. 

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We have already determined 20V is not reaching the battery.   :)

 

 

After we get these results we'll have a better idea of what's going on. 

 

 

There should not be 20 volts ANYWHERE in an SG circuit so its not a matter of IF its reaching the battery.

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If 20 volts is reaching the battery, the SG is not being controlled by the regulator.

 

Hey it's ok, I was just quoting you.  :)

 

 

What happened to the 12.6 at the battery Coley?  Is it fluctuating?

Edited by Geno
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9a09be13eb47ad7b89f936a716e4ff09.jpg

well 22 volts haha

 

 

Not surprising it your reg is grounding the F terminal

 

or

 

the field coil is shorted to the case of the SG

 

lifting the wire from the F terminal will tell us which one of those possibilities is in play.

 

 

IF that same 20 volts is NOT REACHING THE BATTERY - then you either have a defective cutout relay

 

or   

 

a wiring issues from the regulator to the battery.

 

Don't stop measuring voltages when you see 20 volts at the reg - measure the battery voltage at the same time and report back.

 

Trust me - when you fix your problem(s), you won't see 20 volts anymore. SG systems work by NOT CREATING uneeded power - not by "blowing off" excess power like motorcycle charge systems.

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thats on the SG in my photo :)

 

If the battery is indeed 12 volts when the reg is 20 volts, the reg is bad (open cutout relay) or wiring between the reg and battery is open. That would be your 1st problem. Your 2nd problem is why the reg is allowing the SG output to go uncontrolled to higher than 14 volts without lifting the ground off the F terminal of the SG. 

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cb4675720fe88f5a0857cfb022b38398.jpg8a1cbdbe01791bcb4be381a13f0b7128.jpg3f7ca22837d1a827029ee39ec9ab9d9a.jpg

this is how it was wired, the new regulator doesn't have four pins. so it looses the cigarette light connection. but the wiring is identical except for the green on the end.

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