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Discussion Starter #1
My last race in I was way down on power and originally I thought that I hav blow another motor but after some trouble shooting the signs are pointing to my Shiva being the cause. Unfortunately Eventics is no longer around but maybe someone out there can help.

The short summary is in My S10 I am running 4 modified Warp 9's controlled by a Evnetics Shiva and 345v of 3 parallel packs of Chevy Volt batteries.

Dyno:
A few days before the race I ran the setup on a chassis dyno doing 2 runs at 3000 amps and got my anticipated results. I got 633hp and 1733fltbs at the wheels. This is uncorrected and with the ebrake dragging putting motor mechanical power at 730-750hp. The logger showed 3000 amps going to 100% PWM and a pack sag down to 277VDC The biggest thing of note was the logger showed from almost the beginning of the run "Controller temp high" starting at 40C and peaking at 56C half way through the pull. Past that the results were very consistent with my 1 mile runs.

A few days later at the pikes peak :

No changes to the truck except a recharge to 343v. Off the line it felt like it was less then half throttle. My throttle is odd so I actually lifted and smashed the throttle again to be sure I wasn't off the pedal. I was way down on power but just kept in it to get 125mph at the 1/2 mile. I have gotten 135mph at 1600 amps so i knew something wasn't right. I had assumed I blew another motor but the gopro under the hood looked great and it still drives fine other then the fact that it only feels like I am getting 1000 amps. The Shiva log says it was delivering 3000amps but the voltage sag and PWM were very small. (PWM never went over 75%) which indicates I was using the power I should. 4.5 sec in the logger showed "Controller temp high" again but at 4.8sec it went to "Running, Controller temp high, Slewrate active". Slew rate shouldn't be active when I am theoretically delivering the 3000a maximum.

I have done troubleshooting since and the motors checkout fine but I am still getting much less torque then I should for 3000 amps. I did some measuring at 700 rpm idle the logger says it's delivering 80amps tot he motor but using my clamp meter I am seeing about 135amps going to the motors. Stalling the motor showed the clamp and shiva didn't agree (my Milwaukee 2238-21 M12 clamp meter only goes to 1,000a)

My best guess is that it's a problem with the current reading so the Shiva thinks it is regulating to what it thinks is 3000 amps but is really about 1/3 that amount. I haven't pulled the Shiva out and opened it up to test the current sensor. I wanted to reach out for suggestions before I did.

Kerry
More info on the youtubes:
https://www.youtube.com/c/EVEngineering
 

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Discussion Starter #2
Dyno Data:
 

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Discussion Starter #3
1/2 mile run
 

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