openinverter forum

I've read topics over on DIYElectriccar about the pros and cons of keeping and ditching the clutch.

I can't decide what to do.
One thing i like about keeping it is the safety feature if the inverter was to fail 'on', it's a mechanical measure to disengage power, but i'm curious, as long as you still have gears, can you not just yank it out of gear? (this could be naive)
Also enables seamless transition from how the car operates now and quicker changing, not that my conversion car is a sports machine!
I figure the fly wheel, pressure plate and clutch disk are small fry weight-wise on a 2 ton project.

Thoughts?

It would be hard to put the gearbox in neutral with a load applied. Anyway, you should have an emergency stop switch within reach for this kind of scenario.

DaveH wrote: ↑Thu Dec 31, 2020 3:01 pm It would be hard to put the gearbox in neutral with a load applied.

Yes, I wasn't sure if I need being naive there

Anyway, you should have an emergency stop switch within reach for this kind of scenario.

OK, does this switch handle the full current or is it low voltage to run a relay/contactor?

It can be either or both. The OpenInverter board has an input which if triggered shuts down all PWM and thus all possible motor power.
An HV emergency switch is used by some builders. The advantage is that it's definitely gonna shut down power, but often it's rather difficult to wire such a thing in place.

Isaac96 wrote: ↑Thu Dec 31, 2020 5:09 pm It can be either or both. The OpenInverter board has an input which if triggered shuts down all PWM and thus all possible motor power.
An HV emergency switch is used by some builders. The advantage is that it's definitely gonna shut down power, but often it's rather difficult to wire such a thing in place.

Well for PMSM not a good idea to trip DC contactor at speed. This can wreck your inverter. I would just shutdown PWM, but beware ! motor still has excitation in that case, so energy will flow through reverse diodes back into HV battery, forced regen.

For ACIM i use openinverter pin to shutoff small relay which shuts off DC contactor. I use failsafe connection.
This means i can a) start inverter by applying 12V through start pin and b) reliably stop DC contactor by removing GND connection though mentioned relay. ACIM motor turns into a bigh chunk of metal if you remove PWM, so no problem...

I will have a the Inverter 12v logic power AND VCU power fed by a common "12v Bosch" relay, kill the power to either, and you have no propulsion.

Granted, the Toyota engineers and Johu have done a lot of work in the background to ensure off means off.

Thank you guys, i need to mull on it!