View Single Post
Old 09-27-2014, 07:10 PM   #24 (permalink)
Join Date: Nov 2013
Location: Australia
Posts: 350
Thanks: 95
Thanked 210 Times in 150 Posts
Originally Posted by freebeard View Post
I think you're right about the 'old, original clutch'.
Could also be caused by the increased torque due to most EV drivers choosing a single gear for most driveing. 2nd or 3rd. Taking off from a stand still in 3rd gear, even though the electric motor has the required torque it may exceed the clutches torque handling abilities. An worn clutch would be even worse.

Originally Posted by freebeard View Post
The reason I ask is I'm following and wonder about the downside of a single-speed, clutchless, electric reverse drivetrain.
I believe the MGR is an AC motor which is much less likely to fail full on. The controller needs to continue to do all its very complex math and timing to keep the motor turning. Maybe if the accelerator pot failed full on it may cause the motor to full on. Luckily Paul thought of that and in Paul's controller (maybe other controllers too) he checks for 100% pot output and detects it as a fault and shuts down the motor. I think full throttle is designed to be reached at 95% (or something around that) so that 100% throttle can be set as a fault condition.

Originally Posted by freebeard View Post
I need to educate myself about contactors. I noticed in Paul Holmes VW conversion he had a lanyard to pull on a shorted plug. But thread like have it in the trunk. Better to have it accessible from the driver's position?
I was toying with the idea of getting the park brake mechanism from an overseas version of my vehicle. Driver on the opposite side, so park brake on the opposite side of the tunnel. Paint it red and mount it on the passenger side of the tunnel. As my battery pack will be at the back under the rear passenger seat (where the petrol tank was) the cable end will be right near the batteries and should be able to join to a shorted Anderson connector. Anderson connectors come in 350amp types and have nice screw holes for attaching one to the end of the cable and the other to the body.
So in an emergency, not just a runaway motor but also a fire or after a collision. Simply pulling the red park brake will cause a physical disconnection of the battery from the rest of the vehicle.
This would be in addition to the emergency stop buttons in the cabin and engine bay. Which are wired in series along with an inertia switch, to the main contactor energise circuit.

Last edited by Astro; 09-27-2014 at 07:17 PM.. Reason: Added inertia switch collision info
  Reply With Quote
The Following User Says Thank You to Astro For This Useful Post:
thingstodo (09-27-2014)