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How to Find Torque or Current commanded from ACR

Actual Torque is reported from the drive into the ACR90x0's "Final Output Signal" parameter (p12319 for Axis0). In Numeric status, it is under Axis Parameters > Monitor Parameters > Final Output Signal. . This is the equivalent of a DAC output value so that +10 is the max (equal to 100% of DMTLIM/DMTSCL for AriesEPL) and -10 is the minimum (-100% of those settings). Multiply by the drive's current scaling to calculate the current demand. To convert from current to motor torque, multiply by the motor's torque constant (typically the Kt value which is amount of torque per Amp). Or for the Aries or Gemini drives, just multiply the Final Output by the DMTSCL.


Compax3-EPL:
When monitoring the 'Final Output Signal' in the ACR9xx0 for a Compax3 axis on EPL, this maps to C3 object 683.1 (EPL object 0x6077) and is "% rated current."

Divide the Final Output Signal by 0.30517 to give fraction of rated current (A factor of 0.30517 is being applied in the firmware.) Divide by 100 as % rated current.

For current: Multiply resultant by C3 ServoManager's Rated Current (at 230, 400 or 480vac). This is the motor's rated current at rated speed, not the stall current (at 0 speed) which drops at higher speed due to spinning losses.

For torque: Multiply resultant by C3 ServoManager's Rated Torque (at 230, 400 or 480vac). This is the motor's rated torque at rated speed, not the stall torque (at 0 speed) which drops at higher speed due to spinning losses.