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Wedge TR8 Alt
- Thread starter DNK
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Hey, Don -
Here's the schematic I've used.
https://www.team.net/TR8/tr8cca/wedgelab/TR8_schematics.pdf
I'll try to check my shop manual tomorrow to see if it's different, unless someone else beats me to it...
Mickey
Here's the schematic I've used.
https://www.team.net/TR8/tr8cca/wedgelab/TR8_schematics.pdf
I'll try to check my shop manual tomorrow to see if it's different, unless someone else beats me to it...
Mickey
TR3driver
Great Pumpkin - R.I.P
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The third wire is generally a 'sense' wire. I'd suggest connecting it, but it just goes to the battery like the larger output wire does. Some folks just jumper it to the output wire at the alternator; but making the connection closer to the battery will help get the battery recharged faster in cold weather (or with heavy electrical loads).
TR3driver
Great Pumpkin - R.I.P
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No, the 'sense' wire carries essentially no current at all. What it does is allow the voltage regulator to not be fooled by the voltage drop through the output (charging) wire. The output wire (which should already be a big brown wire) is no doubt the one Dan said to beef up, since it has to carry the entire output current of the alternator.
However, IMO the proper use of the sense wire reduces the need to upgrade the output wire. With the sense wire, the output wire only has to be big enough to not overheat at max alternator output; it doesn't matter so much if there is some voltage drop. But with the sense wire jumpered to the output terminal at the alternator (as ISTR Dan suggests), any voltage drop in the output wire will reduce the voltage the battery sees, which will slow the recharging process.
However, IMO the proper use of the sense wire reduces the need to upgrade the output wire. With the sense wire, the output wire only has to be big enough to not overheat at max alternator output; it doesn't matter so much if there is some voltage drop. But with the sense wire jumpered to the output terminal at the alternator (as ISTR Dan suggests), any voltage drop in the output wire will reduce the voltage the battery sees, which will slow the recharging process.
TR3driver
Great Pumpkin - R.I.P
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The output wire (which you already had) is the one Dan talks about running directly to the battery. His opinion (unlike mine) is that it doesn't matter where you run the sense wire (which is the one you are adding) as long as it eventually connects to the battery. IOW, he feels that jumpering the sense terminal directly to the output terminal at the alternator is adequate.
Either setup will work fine; and most folks will never notice the difference. My opinion is leftover from the days when I would start my TR3A from cold, drive about 5 miles to work and shut it off. 8 hours later I'd start it again, and drive home with the headlights, heater and frequently wipers running. In order to use the battery for all those cold starts & short trips, I needed a setup that would CHARGE. With the remote sensing, the alternator would peg the 60 amp ammeter at every start then taper off within minutes. Without it, I'd only get maybe 30 amps and it wouldn't be charged by the time I got to work.
Either setup will work fine; and most folks will never notice the difference. My opinion is leftover from the days when I would start my TR3A from cold, drive about 5 miles to work and shut it off. 8 hours later I'd start it again, and drive home with the headlights, heater and frequently wipers running. In order to use the battery for all those cold starts & short trips, I needed a setup that would CHARGE. With the remote sensing, the alternator would peg the 60 amp ammeter at every start then taper off within minutes. Without it, I'd only get maybe 30 amps and it wouldn't be charged by the time I got to work.