MAC Charger for Yamaha SCR481717

[rockfordpi]

I am trying to determine if the charger per above and attached pics is bad. It is for a disabled gentleman on a very limited/fixed income and I want to be 100% sure before I advise him to buy new. Someone 'worked on it' prior to me.

By jumping the relay, I can get 56v AC output from the secondary to the SCRs. No DC conversion. DC Fuse is good. It appears SCR's are not firing. Could that be because of the issues below:

1. Per the attached pic, can anyone tell me where the terminal on the white wire shown should connect?

This terminal appears to break off of the white A/C input wire prior to the primary. The wiring diagram looks like it shows it connecting to the A/C circuit breaker. However, there is no terminal there to connect to and also, looks like that would be a dead short if there were.

2. Per the attached pic, the side of the shunt wire that connects to DC negative out is not connected. I assume it connected to the heat sink like the other end of the shunt?

However, the standoff is missing, not sure if that was an insulating standoff, or if I could connect that wire directly to the heat sink without a standoff ( I get continuity between the other end of the shunt wire and the heatsink on that side)

20201129_111936.jpg

20201129_111748.jpg

scr (2).pdf

[cgtech]

I cant tell you if it's broken by a picture, but, heres some MAC test procedures directly from them.

[plowman]

well if you don't fix it i have used oem chargers for 100.00

[rockfordpi]

Originally Posted by plowman

well if you don't fix it i have used oem chargers for 100.00

I actually called and spoke with a lady at your place earlier today and also forwarded your phone number to the end user.

A couple of questions I did not understand and will need to relay info to the buyer. The lady said it would be $35 more to add the MAC plug to the charger. Is this for plug and cord or just plug?

He already has a charger cord with MAC plug from his old charger, how difficult will it be to install his on one of your chargers.

[rockfordpi]

Originally Posted by cgtech

I cant tell you if it's broken by a picture, but, heres some MAC test procedures directly from them.

I may have it working. I have not worked a lot with SCR chargers, only diode chargers. Apparently, you can't simply jumper the relay on this charger and make it put out DC voltage like a diode charger. If I understand correctly, the board still has to see min voltage before it will fire the SCR's.

I only had the charger, no cart to check it with. However, I used two cheap jumper wires to connect to another brand cart (BBB) and was able to make the charger come on before the jumpers burned up. I never actually saw 56 volts, the most it got to was 51 volts, but I think this may be due to the connection (which was to a nearly drained T-145 pack).

I am still going to suggest he get one of Plowman's used OEM chargers if he can possibly afford. That is a HECK of a deal.

Oh, and the missing white wire went to the Varistor, according to MAC it would be OK to run without the Varistor protection in this case.

Thanks for the response!