Dia. Mag. Alternator

[z.monkey]

Three is wound...

Waiting for the epoxy to cure...

[nievesoliveras]

Wish for the best!

[z.monkey]

OK, cracked the core out of the winding jig this morning.  I spent a couple hours reassembling the thing, and now I have some test numbers.  So, I am going to summarize the results of the three windings here.

Coil 1, 26 AWG
Coil resistance = 25 Ohms x 2 coils in series = 50 Ohms.
Open circuit voltage = 17.34 Volts.
Voltage Loaded with 65 Ohms = 5.84 Volts.
Amperage based on resistor = 89.8 milliAmps.
Wattage based on Amperage = 0.52 Watts.

Coil 2, 14 AWG
Coil resistance = 0.6 Ohms x 2 coils = 1.2 Ohms.
Open circuit voltage = 0.73 Volts.
Voltage loaded with a 65 Ohms = 0.63 Volts
Amperage based on resistor = 9.7 milliAmps
Wattage based on Amperage = 0.006 Watts

Coil 3, 22 AWG
Coil resistance = 2.5 Ohms x 2 coils = 5 Ohms
Open circuit Voltage = 3.85 Volts
Voltage loaded with 65 Ohms = 3.17 Volts
Amperage based on resistor = 48.7 milliAmps
Wattage based on Amperage = 0.154 Watts

If we look at the wattage, the first coil looks like the best.  But, look at the way the voltage drops off under load.  Clearly a current deficiency.  Coil 2 is simply mismatched.  6 milliWatts, uulgh...  The third coil develops a low voltage, but doesn't fold when the load is applied.  So, of the three the third coil is probably the best matched of the three...

So, I think I am satisfied with the coils now.  I'm gonna work on some other parts now...

[z.monkey]

Something that has been bugging me for a while is the Flux Return Path Bars (FRP-Bars).  I needed to improve the flux pathways around the outside of the coils.  There are currents there, and they need a highly conductive path around the outside of the coils.  These are the "I's" that I was talking about before.  The I's that are missing from the EI cores...

I got a bar of mild steel which is 1/2 inch x 1 inch x 3 feet, about $18 at Ace Hardware.  I cut some 7 inch sections.  I put one on each side of the core, and then clamped them into place for a test.  OK, now look at these numbers...

Coil 3, 22 AWG
Coil resistance = 2.5 Ohms x 2 coils = 5 Ohms
Open circuit Voltage = 7.81 Volts
Voltage loaded with 65 Ohms = 5.71 Volts
Amperage based on resistor = 87.8 milliAmps
Wattage based on Amperage = 0.501 Watts

I tripled the output wattage by adding the Flux Return Pathway Bars (FRP-Bars)...

[z.monkey]

I made a video of the test and put it on yuo tubez...

http://www.youtube.com/watch?v=1vmkOOXpGRE