B+ Shows negative DC Voltage

bob54

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Have it installed on a zero turn mower that a computer controlled fuel injection system. I eliminated the computer installed the KT745 which has a carburetor and it works great. Problem I am having is hooking up the charging system. I am getting 14 volts on the B+ side of the regulator but when I test it with a digital volt meter I have to have the Neg lead on the meter on the B+ and the Pos lead on the neg terminal of battery or grounded to the mower. If I reverse the Leeds the meter shows a negative sign in front of the voltage on the meter. Any Ideas?
 

Rocky J

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with it running and you put your test meter on the battery + to + and - to - what reading do you get?, make sure you meter is set to DC
 

bob54

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I get 12.56 volts DC. I do not have the charging system hooked up yet since I have to have the negative meter lead on the B+ from the regulator and the Positive lead to ground or the meter shows -14.5 volts DC. The Stator and regulator seem to working fine. I am just confused by the way meter has to be hooked up. Do I hook the B+ From the regulator to Positive or negative for charging?
 

cpurvis

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Hook up everything and check with all wires in place. If you have the voltmeter in series in a charging circuit, nothing is going to get through to the battery.

You already know what the battery voltage is with the engine off (12.56). With everything hooked up, start the engine and check it as Rocky J said. That will tell you if the battery is being charged if the voltage is higher than 12.56v.
 

bob54

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I have not hooked the charging system to the Battery because of the lead connection problem with the meter I wasn't sure it was a good idea to hook it up to the Battery
 

Rocky J

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I have not hooked the charging system to the Battery because of the lead connection problem with the meter I wasn't sure it was a good idea to hook it up to the Battery
If the engine is not running and hooked up proper the current would be coming out of the battery and you would see the - negative meaning discharge , you need to hook up your wires and have the engine running to see the + positive meaning the current is going into the battery from the charging system.
 

NorthBama

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check your meter on another battery
 

Telesis

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Just for the sake of clarity, let's just stick to measuring Voltage, and NOT Current. When measuring the voltage, make sure your meter leads are in the proper place on your meter, and you are on a DC Volts scale of at least 20VDC. Connect your black meter lead to the negative terminal of the battery(or arguably a good ground), and make all of your measurements with the red meter lead. It appears from your posts that the battery voltage (w/o charging lead connected) is about 12.5 VDC. The B+ lead of the regulator(when connected) eventually makes its way to the Positive lead of the battery(perhaps through the Ignition Key Switch).

With the engine running, and your red meter lead on the positive battery terminal(black still on the negative), when you connect the B+ terminal from the regulator, you should see the measured voltage go UP. It will likely exceed 13VDC or perhaps a bit more. If it goes up to a value above about 14.8VDC, your regulator is probably bad. If indeed it goes up, it's a good bet your rectifier/regulator is doing it's job and you're good to go! If you do NOT measure a change, the regulator is likely bad OR there is a wiring problem.

At all times you should be measuring a Positive voltage with the meter leads connected as described. Without having a load of some kind from B+ to ground, trying to measure the output of the regulator while it's disconnected can produce goofy results. Connecting the output to the battery will tell you whether it's working.

Checking the charging circuit by measuring the voltage is, in this case, the best way to test it. I would not recommend trying to measure DC current as this can vary greatly depending on condition of the battery, engine rpm, etc.
 

cashman

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For a load test, I used a 12V 60 watt rough service light bulb mounted in an old wall pack light fixture. Kohler always recommended running the B+ to the "R" terminal on the ignition switch which disconnects the regulator from the battery when the ignition switch is in the "OFF" position. It's best to not have the regulator/rectifier continuously connected to the POS battery terminal when not in use.
 

ILENGINE

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For a load test, I used a 12V 60 watt rough service light bulb mounted in an old wall pack light fixture. Kohler always recommended running the B+ to the "R" terminal on the ignition switch which disconnects the regulator from the battery when the ignition switch is in the "OFF" position. It's best to not have the regulator/rectifier continuously connected to the POS battery terminal when not in use.

Wrong, Kohler had told their dealers to clip the purple wire that goes to the key switch and wire it directly to the B+ side of the starter solenoid. Kohler does not want the charging system going through the key switch. has to do with the possibility of voltage spikes damaging electronic components. One of the ignition module conversions had specific instructions to move the purple wire from the key switch to the starter solenoid. Even came with the eye terminal to crimp on the newly cut wire.
 
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