Ohms affected by temperature?

vim420

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Im troubleshooting my charging system according to the manual. One test is to check the resistance between the three white wires. In the manual it says that the measurement is affected by temperature and should taken into account. So for me the resistance read was one ohm across all wires and i was in the shade when it was 16C out. Manual says 0.75 with a variance of 10% at 20C. How much will temp affect my readings?
 
Temperature can definitely change resistance, but I can't see 4 degrees making a significant difference. Perhaps wait for one of the electrical gurus to chime in though ;)
 
Don't get too excited about the exact measurement unless you have a certified and calibrated multimeter with fresh batteries. As long as the readings are close to spec and virtually identical, you should be good.
 
Alright thanks! So with your guys expertise would you say its the alternator thats dead? I tested the rectifier, it works. I also tested the field coil and it seemed okay. fully charged battery at idle is at like 11.9v. When i unplug brake/headlight it goes up to 12.2ish. With change in rpm it goes up a little no where near 14.5 at 5000rpm though. Thanks for the help! would like to get some riding in and not spend all summer in the garage!
 
I spoke of doing ohm testing in your other thread. I might suggest reading it and retesting.
Also how good is your battery? The field coil draws power from the battery to create electricity. Try fully charging your battery. No car chargers, use a motorcycle charger. Around $20 at Wal Mart. Schumacher SEM-1562A.
A low battery won't provide enough power to get the alternator working.
Leo
 
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