Dave Posted July 20, 2002 Share Posted July 20, 2002 Actually its the alternator that needs the work. I have a CS series alternator that I need to break the field circuit in when I hit WOT. I have electric fans, water pump, fuel pump and ignition that are drawing close to 40 amp. By breaking the field circuit from the regulator in the alternator at wide open throttle there is nothing belt driven that eats up horse power. It looks like from this site http://www.transpo.de/cgi-win/product.exe?D7050 the one wire conversion has had the regulator moved to the outside of the alternator. Has anyone done the one wire conversion on a CS series alternator? The cs series is the alt that has the serpentine belt. Quote Link to comment Share on other sites More sharing options...
Mike C Posted July 22, 2002 Share Posted July 22, 2002 I assume you are trying to free up a few extra ponies at WOT? It may be in your best interest to NOT disable the field as you will drop from 14.4 volts or so down to 12.6 (fully charged batt) which can lower your electric fuel pump and ignition output significantly costing way more power than switching the alternator would allow. Quote Link to comment Share on other sites More sharing options...
Dave Posted July 22, 2002 Author Share Posted July 22, 2002 My ignition (Mallory stuff) is running at 9V all the time set with a electronic regulator. I have a Meziere electric water pump. I can take the fan belt off the car and it runs just fine off the battery. Fuel pressure is fine at full throttle. I am after the 7-10 HP the alternator is using. I did this years ago with a 66 Vett using a relay and a TH400 kickdown switch to break the field from the external regulator. The SI and CS series internal regulator alternators are not making this easy. Quote Link to comment Share on other sites More sharing options...
Mike C Posted July 22, 2002 Share Posted July 22, 2002 If you alternator is a 3 wire, one of the two smaller should still be a field wire and the other an indicator wire. Separating the two and installing one at a time should see which identifies the field wire. Actually, with the ign switch off, they should both be dead, and with the switch on, the field wire should be hot. I'm not sure what sort of feedback is used for the indicator but would assume it is LACK of voltage that triggers idiot light so that one would be dead with engine not running. Check out Powermaster's web site and see if they have instructions for their alternators. They allow 1 or 3 wire hookup on most of them and that should help you id the field wire. Quote Link to comment Share on other sites More sharing options...
pparaska Posted July 22, 2002 Share Posted July 22, 2002 I'll look at my paperwork at home. The CS alternators have I think 1 large and 3 smaller pins in the connector. I'll find my notes and find out which is the field wire. I agree, you could use a switch on the field wire to cut power. The field wire from the alt is very near ground when it's not turning, and near the output voltage when it's charging. If you open that while it's running, it should cut the output power and the drag on the motor. I'm not sure if that's hard on the electronics in the alternator though. BTW, the CS is a nice design - clean filtered output and lots of amps even when it's spinning slow at idle. Way expensive though. Isn't the field wire actually the indicator wire? I mean, I only used the field wire on my CS130 and it's hooked to 12V with the key on through and idiot light. (I like having that feedback, myself - nice to know when the alt's not putting out!) The voltage feedback wire is actually handled internally, eventhough it has a terminal on the alternator. I got that info from M.A.D. Enterprises in CA. He's done alot of research on these alts and even helped GM straighten out their databases on the alternators. The only wires you need to hook up on a non-one-wire CS is the field wire and of course the output wire. Quote Link to comment Share on other sites More sharing options...
Dave Posted July 22, 2002 Author Share Posted July 22, 2002 The SE three wire only needs the S and the F terminals for our cars. The S is the sensing that is connected directly to the output from the alternator. The F is the Field that excites the Rotor (field) through the charge indicator light. I see from Powermasters web page that their alternator will drop a couple volts when the field is taken to ground but this recovers only a couple HP. Call it greed on my part but I want all of it at WOT. I found the wiring schematics for the charging circuit on the SI http://12.224.138.56:8884/delcosi.jpg and it looks like I have to break both the Sensing and Field circuits but the Diode Trio is still feeding the internal regulator. If this works the alternator will stop charging at a low RPM but it will come back to life just off of full throttle. The External regulated Ford and Chevs I have done this on in the past had point type regulators. The CI and SE with their electronic regulators may not be able to handle this. I may have to try a Ben Franklin and fly the kite in a thunder storm to get a answer if this will work. I haven't done anything quite yet, but its getting close. Quote Link to comment Share on other sites More sharing options...
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