Trouble shooting with Alternator exciting

Step by step instructions.

1.Disconnect any caps at ALT.

2.Use crocodile clip and connect the multi meter leads to L1 & L2 at ALT. Set the multi meter to 600VAC and not DC.

3.Now take another two crocodile clip and connect your caps at L2 & L3. Leave the cap clip connected at L2 but disconnect L3.

4.Now start your PM and get the max RPM. Very important.

5.Now touch the other cap clips at L3 and wait for a moment. Or you may just leave it on and wait for a moment.

6.Watch your multi meter and check if the voltage rise above 100V. If after 10 seconds and still no sign of voltage increase then just off the PM.

7.Go increase the cap value then repeat steps from step 1 until you can see some voltage increase.

The humming sound or voltage increase then your are done. The motor acting as generator. Just use rubber gloves when clipping the caps to the motor leads.

If you planned to add more caps without switches, make sure you discharge the caps before and after touching the permanently attached caps to alternator.

Example using 130 uF attached

Now you have 130uF attached to alt. Take another 10uF caps then touch both cap leads to 130uF cap bank leads. Hear the sound of ALT if changes or not. To be more accurate, check AC voltage at any two leads from ALT. If the it goes above 100V, yes the ALT is started generating.

If doesn't work, discharge the 10uF caps then add another 10uf caps to make it 20uF. Now again touch both cap leads to 130uF cap bank leads.

Make sure the PM runs at max RPM. Normally when we add caps at alternator, it takes some time to start generating. few seconds unless the caps value is big enough. Be patient.

Alternatively.

On the alt just put a cap box on it and a scope (might want to resistive divide the signal to stay in scope range)and switch the caps in one at a time then you should see the alt come to life. If not zap a phase with a 12v bat into the alternator windings to allow the residual magnetism to build up and try again. P.S. if you grounded your rig you might want to float your scope ground.

If you need to add more caps, just touch caps leads at alternator caps connection. You don't have to open the cap bank boxes. Just connection points which goes to ALT leads. NOTE - If you touch the caps leads, the blue spark can be seen and the sounds like fire cracker. Don't be scared as long as you use rubber glove, you are safe.

2 other Options:

First:

The experimenter describes that his alternator was 3000 rpm as well, wired for 380 volts. And used 80 uF capacitance to get resonance with single phase. If your alternator is wired for 110 Volt, you could need more capacitance. than 120 uF (Depends on grid frequency too).

you will definitively need more than 80 uF. And I think you will need even more than 120uF.

But!!!

If you read 0 Volt AC (not 3 Volt or 2 Volt, but ZERO VOLT), you could have

a short-circuit in your cap bank. Check this.

If cap bank is ok, your alternator core is fully de-magnetized. You need a small magnetic imbalance in rotor to get alternator to work. Remove the wires from your alternator. Take a car battery and 2 wires, and touch for about 1 second 2 of the 3 phases with battery wires. This should re-magnetize your alternator rotor. Rewire the alternator and test again.

Second:

If you can read some low voltage, your capacitance isn't correct. Tune it towards higher voltage by adding more capacitance.

If the alternator is wired to 220V, its better as gives more inductance where you need less capacitors. RPMs higher than 50cps are even better what I've found out.

One tip - if you need to start the system to GENERATE use something like 100uF capacitor in series automatic mechanical FUSE (5A or so). Then the rest of the 30uF caps are in parallel.

If your alternator starts to generate finally - 100uF caps will be too heavy and will certainly lug it down, usually it requires fast kung-fu skills to switch it off at the right time and let only 30uF (cap bank) to keep it working. If you're not fast enough you need to spark the alternator with battery to make it magnetically alive again. An 'auto-fuse' may save you from those problems.

The lower the voltage the higher capacitance the narrower tolerance and hi Q

cut off sensitivity , will be harder to tune it Specially in reverse induction modes unless using PM rotors. Its normal for alternator to take 10 to 30 seconds starting at selected capacitance value, no need for instant boost ones. unless you degaussed dead by overloading.

From another angle and method

To get it to alternate the first time or two you almost need to shock the alternator, that is, no caps hooked up to alt at start up (or stop, in a minute) Bring it up to full speed, THEN switch in capacitor. It takes a few seconds. if you've got it right, then she will squat down and grunt! Look for a definite pitch change from benign to a meaty growl.

If you go TOO big you will stall the PM, no big deal BUT stalling it under load can sometimes (most times) de magnetize the rotor. So always remove the load on the alternator before you shut down the PM.

Check also that your cap box is parallel switched not series switched.

And that there is no miss wring.

If all else fails.

If using the same motors described and recommended.

revise the internal phases wiring numbers. Star (WYE) low voltage alternator wiring Group (4,5,6) centre wye common. remember there is another internal wye centre non connected to this one )then Phase A (1,7) phase B (2,8) Phase C (3,9) Check continuity of lines 1,4 2,5 and 6,9 if 2 are open try to trace to another if one is open you are in the wrong and have got an internal open lines 7,8,9 will read to each other if no, then you are twice in the wrong as you have got an open inner star. check this and try again.