fechter wrote:I think he wants to do the opposite.
I've never seen one of those controllers first hand. It would be v1 of sorts.
Look on the board and see if there is a 16 pin chip marked C1246. That's the commutator chip used on the immediate start controller. If it has one, then there should be a way. I've never fully traced out the hall sensor input circuit, so I don't have a schematic of that part (it may be posted earlier in this thread?).
From my post on the V2 controller thread: Those 3 holes on lower left look like place to attach 3 hall wires. Underneath there is a 16 pin chip that I'm guessing is upc1246 commutator. I can only see "6G" or maybe "6C" ? at end of chip number. Those 3 holes: 1 goes to pins 1 and 4, 1 to 3 and 6 and other probably to 2 and 5 so it looks like commutator chip there.
So if I can figure out the right wiring for 3 hall sensors, I just add ground and some suitable voltage point, presumably another hole near these 3, or same voltage as throttle ?
Here's the response I got from ebikes Justin:
I've never heard of anyone converting a PF to an Instant
Start model. Depending on how the board was designed it could be as
simple as attaching the 3 hall signal lines, but that isn't too
likely. If you reverse engineer the layout and figure out how the
commutation timing circuit is implemented then you could come up with
a hack that drives the phase decoder chip from the hall lines instead,
and if it is indeed using an actual hall decoder commutator chip then
this might not be that difficult, and would be a neat feat.
So maybe I'll be the first to try this mod. I'm pretty sure it's possible now. Those 3+ holes ARE there for hall sensors and I suspect there is an instant start version of this board; I just have to figure out wiring and hope it just works without messing with any jumpers for mode select.
This IS a Crystalyte controller, bought from ebikes 1 month ago. 72v, 20a, pedal first. Sort of an oddball in the lineup IMO, because it's a 72v unit but only rated for 20 amps ? Seems funny to have 12 4110 fets but only 20a limit.
No clear markings I could really see. Will check much closer next weekend when I pull the controller and try to add this mod.