7circle wrote: Have checked out the Curtis website.
They have a section for the 1238-75. Maybe the model name variation makes it hard to find.
And Data Sheet 1238-75
But they only refer to volatge range of 72-96V. and 2min RMS Power Rating 62.3 kVA.
Being such a compact controller requiring heatsinking, it would be useful to know what size/rating DC capacitor bus is used.
If the controller was operating close to peak voltage supply extra DC bus capacitance may help protect against battery & cable circuit inductance overshoots.
Under regen the bus voltage may also be driven high and beyond Max causing damage to controller.
I was impressed that thunderstuck site provides a spreadsheet of an analysed system. Power Curve AC-50 (?? 1238-7501)
Is this the info you need?
Thanks for that 7circle. That was very helpful - and yet it raises more questions.
The "System Voltage" is 72 - 96,
The 2 min RMS Current rating is 550 Amps
The 2 min RMS Power rating is 62.3kVA
I'm not quite clear what "System Voltage" is - possibly the voltage seen by the motor rather than the battery voltage. Is that right? and the KVA multiplied by the PF gives the actual KW of power is this right? I apologise if I'm a bit slow here but Uni was a long time ago and I'm not familiar with some of the Jargon.
I understand that if you want to push the voltage/power limits of this controller you definitely want to do some heat sinking along with fans or water cooling.
Looking at the full manual for the other 1238 controllers - they seem to have lots of protection built in for things like the maximum regen voltage, so I think this should be manageable.
I've heard that the bateries used for the Thunderstruck test were some old lead acids, hence the sag at max power. I think Thunderstruck are into performance EV's. They must have a dyno availabe to have done the test.
Thanks again for your help 7circle.