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Limits and Warnings

Peripheral speed warnings

If required peripheral speed warning limits may be configured:

Commands Type Required Description
low_controller_X_speed_warning_h float32 Optional Peripheral speed high warning (Rad/S).
If the peripheral speed rises above this value, the velocity warning flag bit in op_state signal will be asserted.
Default value: 10000 (Effectively disabled)
low_controller_X_speed_warning_l float32 Optional Peripheral speed low warning limit (Rad/S).
If the peripheral speed falls below this value, the velocity warning flag bit in op_state signal will be asserted.
Default value: -1 (Effectively disabled)

Notes:

  • The velocity warning flag bit in op_state signal is shared for both channels.
  • The peripheral speed warning bit is only set while a channel exceeds the limit. It does not latch.

On E-Stop behaviour

Under E-stop conditions it is desirable to have the thermal manager continue to run to ensure the system remains within safe thermal bounds. Unfortunately, under E-stop conditions external temperature or control signals may not be available, and thermal management authority may be lost.

The thermal manager has the option to set a fixed PWM duty cycle value to the outputs in the event of an E-stop. The PWM duty will remain at this value until a jcs_host reset() is issued and the E-Stops are cleared.

Commands Type Required Description
low_controller_X_on_error_pwm_duty float32 Optional PWM value to set to output X if an E-Stop occurs.
X is channel 0 or 1.
Default value: 0.75 (75%)
Valid values between [0.0f, 1.0f]

DC Bus current sense filter

If required the peripheral DC bus current sense 1st order low pass filter cutoff may be configured:

Commands Type Required Description
i_dc_X_filter_fc_hz float32 Optional DC bus voltage filter cutoff frequency (Hz).
X is channel 0 or 1.
Default value: 50Hz

Channel current limits and warnings

If required both channels may have their current sense limits and warning configured:

Commands Type Required Description
i_dc_X_limit_warning_h float32 Optional Channel X current high warning limit (A)
X is channel 0 or 1.
If the channel current rises above this value, the channel X current warning bit in op_state signal will be asserted.
Default value: 2.0V
i_dc_X_limit_warning_l float32 Optional Channel X current low warning limit (A)
X is channel 0 or 1.
If the channel current falls below this value, the channel X current warning bit in op_state signal will be asserted.
Default value: 0.0A (Effectively disabled)
i_dc_X_limit_error_h float32 Optional Channel X current sense high error limit (A).
X is channel 0 or 1.
If the channel current rises above this value, an E-stop will be generated and the device will shutdown all outputs.
Default value: 3.0A
i_dc_X_limit_error_l float32 Optional Channel X current sense low error limit (A).
X is channel 0 or 1.
If the channel current falls below this value, an E-stop will be generated and the device will shutdown all outputs.
Default value: 0.0A (Effectively disabled)

WARNING:

It is possible to set the channel current error limits to a value larger than what the channel can actually support. This can result in damage to the hardware. It is advised to NOT set the high error limit beyond the default value.

Channel current sense filter

If required both channels may have their current sense 1st order low pass filter cutoff configured:

Commands Type Required Description
i_dc_X_filter_fc_hz float32 Optional Channel current sense filter cutoff frequency (Hz).
X is channel 0 or 1.
Default value: 500Hz