Been there, done that (in my ‘evil’ youth).
The problem comes with the speed control.
If you have a 36V solid-state speed control, it doesn’t care if it has six 6 V or three 12 V.
Post the wiring diagram or a link.
My challenge (in 1963) was I had four 6 V batteries and a 12 V motor.
Control was 6 V (all batteries in parallel) to the 12 V motor for ‘low’ speed.
‘High(er)’ speed was with each pair of batteries in parallel and the two ‘doubles’ in series for 12 V to the 12 V motor.
Control was by several 6 V relays (contactors).
Well this wasn’t fast enough for me to navigate the GE Appliance Park (nine 1,000,000+ sf buildings) at 3 AM.
‘Simple’, I rewired it for 12 V to the 12 V motor on ‘low’ and 24 V to the 12 V motor on ‘FAST’.
I just had to be careful to not pass any ‘suit’ too fast.
More to the story.
The contacts in these relays were serviceable.
Needless to say, I went through contacts.
The problem was they were pure silver.
The maintenance departments weren’t happy about the cost.
The ‘solution’ was to insulation wrapped refrigerator door ‘U’ magnets (plentiful supply from the refrigerator department).
Add some phenolic brackets to maintain the “Right-Hand Rule” across the contact’s opening.
Presto, no more severe contact erosion as the perpendicular magnetic field ‘blew out’ the induced arc.
The 12 V motor was so conservatively rated, it took the abuse.
When I was just about to return to Carnegie Tech, I submitted the idea as an “employee suggestion” (
after re-wiring to original).
After a fancy presentation, I got one of those BIG checks for $35,000.
That was a LOT of money for a 20-year old in 1963.
I invested it.
GE saved millions.
I paid cash for my first new 911 in ’68 and an RS-60 and a 904….
Best,
Grady