DIY Volt Hybrid - Open ReVolt style

[jackbauer]

First thing i'd say is to take a few pictures of the inside of your charger so we can see how it operates and maybe diagnose the problem and/or point out a few tests. I seem to remember from your videos that its a Lester? If so it will be something like a simple scr rectifier so should not be a big deal to repair.

The ideal plan would be to have the genny charge the pack directly and vary revs acording to load. This means you don't use a charger at all but use the engine rpm to regulate the output. I'm aiming for something like this but mounted on a trailer. It all depends of the design of the generator. Does it change speed to match loads? Ie if you plug something in does it increase rpm?

[MetroMPG]

Ben! Congrats on making it as a finalist!

I voted! Everyone vote for Ben!

[bennelson]

You can see some photos of the charger at:
MobileMe Gallery

The generator does increase speed to power larger loads.

The generator has a stepper motor with a linkage to the throttle. The control circuitry runs the stepper motor to control the throttle, and increases throttle when there is a higher amperage demand. I wonder if the generator would work properly with the linkage between the throttle and stepper disconnected. I could instead have some sort of a manual throttle linkage in place. I don't know if the generator would sense this as some sort of error and shut down, or if it would allow me to do it.

If I could remove the linkage easily, (so it could be hooked back up without any permanent damage) that might be interesting to try.

[jackbauer]

Ok from the photos what i think you have is a single scr charger. Quite a smart little design. On the black heatsink beside the bridge rectifier (black square) you should see the scr. Can you read the part number and post it here? That scr is what controls the output current and voltage. Chances are its failed and backfed power to the firing circuit on the pcb and thats what killed your resistor. A simple test is to short out the anode to cathode. Charger should run at full power. Be carefull if you try this as its not isolated from the mains.

[bennelson]

You can see a PDF version of the charger manual at Mr. Sharkey's web page.
LINK

Unfortunately, it's just the owner's manual, not a repair manual!

I CAN see some lettering on the side of the SCR, but it is small and sideways. I don't think I will be able to read it without removing the SCR. Is there a right way to take that out?

If I do take it out, is there an easy bench test to do on it while it is removed?

Also, there are three legs on the SCR. One is skinnier than the other two and doesn't have as thick wires going to it. Is that the "gate"?

[todayican]

Darn, and here I was ready to travel through space and time :-(

[jackbauer]

Yeh the thin wire is the gate. If you disconnect the gate you can probably test the scr in situ with a meter. This page has some good information and diagrams:
The Silicon-Controlled Rectifier (SCR) : THYRISTORS

Depending on the device you can wire a resistor between the gate and anode and it will fire manually. This would at least prove that the scr is ok and the problem is in the firing circuit.

[bennelson]

I haven't had much time lately to work on the charger. I hurt my hand, have a baby to take care of, and have been busy with a couple other things as well.

Trying to get this charger figured out is the next step.

However, in the big exciting news department, please visit INSTRUCTABLES.COM and tell me I am reading the results of the Craftsman contest right!

[MetroMPG]

Wow!

Grand Prize
DIY Plug-In Hybrid Car

Congrats Ben!

[MPaulHolmes]

Ben, no one else even stood a chance. Make sure you save $6000 to pay the taxes. haha.