Frankenrunner User Manual
Rev 1.0
5.3 Battery Limits
Basic Setup tab
With the controller mapped to your motor and spinning correctly, you should now
set the battery voltage and current settings to appropriate values for your pack.
Set “Max Battery Current” to a value that is equal to or less than the battery’s
discharge current rating. Higher battery currents will result in more power, but
can also stress the battery cells, resulting in shorter battery life. Excessively high
values can cause the BMS circuit to trip, shutting down the pack.
We recommend setting “Max Regen Voltage (Start)” to the same value as the full
charge voltage of your battery, with the “Max Regen Voltage (End)” to about 0.5V
higher than full charge. This will ensure you can do regen even with a mostly
charged battery.
The “Low Voltage Cutoff (Start)” and “Low Voltage Cutoff (End)” values can be
set just above the BMS cutoff point of your battery. If you are using a V3 Cycle
Analyst, we recommend leaving these values at the default 19.5/19.0 volts and
use the CA3’s low voltage cutoff feature instead. That way you can change the
cutoff voltage without a computer if you ever need to swap batteries.
If you are setting up a system with regenerative braking and have a BMS circuit
that shuts off if it detects excessive charge current, you will also need to further
limit the “Maximum Regen Battery Current” to a value lower than the BMS trip
current. Otherwise it's not usually an issue with modern lithium cells to have short
duration peak regen current levels of 2C, ie double the battery amp-hours.
5.4 Motor Phase Current and Power Settings
Basic Setup tab
In addition to regulating the current flowing in and out of the battery pack, the
Frankenrunner
can independently control the maximum phase currents that flow
to and from the motor. It is the motor phase current that both generates torque
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