Replaced the Dynamo.. Now puts out 20V (AC) @ high rpm.
Checked output of old regulator.. should be 14v it was <1v
good voltage going in. nothing coming out.
Replaced regulator @ $73 and change.:-(
put in new regulator.... same voltage (<1v) out the dc end.
again: good voltage going in. nothing coming out.
Ok I need to find out if I had a (new) bad regulator or ??
Need to fix the problem before I 'do' another regulator.
I've checked out both regulators with multi-meter (as if they are simple full phase rectifier.) both are bad.
Tractor starts hard (with jumper to car) and runs fine.
Can you point me to the possible problem areas.
Also: Is it possible to put in an old type voltage regulator (non-solid state) to get this running?
Thanks, Ron
Ron the bottom line is like you said the battery poles should be seeing any where from 12.9 volts DC at low idle to 13.94 at high idle and the fact that you are burning out regulators ( P/N 15372-64602 ) tells me you have a dead short allowing overcurrent to destroy the transistors, diodes and capacitors internally in the solid state IC regulator.
Lets start with some basics...
open the attached simplifed diagram of a basic charging system from Government Motors
HAHAHAHAHAHA!
Your Voltage Regulator tries to get the battery and the Alternator to work together for the charging system. The battery carrying the load when the RPM is low and the charging system taking over when the alternator is at high output. Bare in mind the Diagram shows an internal voltage regulator but in reality yours is a separate box outside the housing.
Notice the idiot light...now when the ignition is turned on the current flows from the battery through the light to the number one terminal on the alternator. This is part of the regulator circuit the same as on your tractor. and current flows through resistor R1, diode D1, and to the base of transistor TR1 on its path to the battery through the ground connection.
This current flow turns the transistor on allowing current to flow through the alternator field coil and to the other side of TR1 before flowing back to the battery. Notice the resistor in parallel with the idiot light reduces the total circuit resistance to provide a higher field current for initial voltage build up when the engine starts.
The heavy positive battery cable is not in the circuit diagram because its not technically part of the charging system but is and will cause problem if cells are dead internally blocking electron flow negative to positive. Once you start your tractor and the AlternaTor is spinning the pully unlike poles in the stator start the AC voltage in direct proporation to the speed of the rotor. The diodes in the rectifier bridge change the AC into DC at the Diode trio at the "BAT" terminal and ground. As the tractor RPM increases so does the ability of the Alternator to supply current to circuit loads, Lights, etc...
Now here's what you need to understand to find your short that's burning out your regulators. With the alternator producing about 20 to 30 volts AC, this same voltage flows across the "BAT" terminal and the number one terminal and the idiot light goes out showing you the alternator is producing power. The number two terminal is also connected electrically to the battery and but the high resistance of R2 in series parallel with R3 limit the discharge current. The increased voltage between R2 & R3 allows diode D2 to flow, turning off transistor TR1 and turning on TR2 until the system voltage matched by resistance in the regulator see a drop below demand and the whole cycle
starts up again when TR1 get flow and starts increasing voltage per demand load. This happens several times a second and thus the IC circuits see heat, lots of heat. The other components within the regulator show a capacitor C1 to stablize the voltage Across R3, the resistor that limits the current through TR1 at high temperatures, and a diode that prevents high induction currents in the field windings when TR1 turns off.
In a nut shell,
the alternator regulator relationship is to control the voltage allowed in the charging system at all times, protecting the battery from an overcharge, and at the same tme keeps the battery voltage from discharging
into the stator winding at periods of low tractor rpm (idle). Specific to your question, yes, you can use an elecro-mechanical regulator with your tractor as long as you wire in your instruments and accessories but until you find the primary short circuit causing the overcurrent draw through your transistorized regulator your mechanical contact points will also fry in time and its hard to tell how many batteries you will run through in the process.
Start a wiggle and pull test looking for shorts to ground. It will show up on your Multimeter in LED movement as you loop through each circuit in the primary start and accessories associated with the ignition switch normal run
position. There's no trade secret here to give out just due diligence with your wiring diagram.
Feel free to send me a private Email if you don't wish to discuss on line Ron. I hate to be long winded on line too.
