paul dove wrote:
> There is no voltage adjustment on input voltage in any motor controller I
> ever used.
This discussion specifically concerns a vehicle using a Zilla motor controller;
from the Z1K specsheet:
"Other features include programmable motor voltage and current limits,
programmable battery voltage and current limits, adjustable low battery voltage
protection and an additional low battery indicator output."
> It may have a low voltage cutoff circuit but that just shuts down the
> output in the event the battery falls below 72volts.... thus the
> controller would not be working if the voltage was 96-72 = 24volts.
Even this simple case would achieve the *same* behaviour: the controller would
PWM "willy-nilly" until the input voltage sagged below the minimum input
threshold, then it go to 0% duty. As soon as it went to 0% duty, the load on
the battery would decrease, and the input voltage would rise slightly above the
minimum threshold, and the controller would resume PWMing.
Resuming the load would sag the input voltage below the threshold again, and
the cycle would repeat such that the input voltage is regulated in a sawtooth
manner at the minimum voltage.
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