Programming 
Page D-126  890CS Common Bus Supply - Frames B & D; 890CD Common Bus Drive and 890SD Standalone Drive - Frames B, C & D 
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SPEED LOOP 
SETUP::MOTOR CONTROL::SPEED LOOP 
Designed for SENSORLESS VEC and CLOSED-LOOP VEC  Motor Control Modes. 
This function block controls the speed of the motor by comparing the actual speed to the demanded speed, and applying more 
or less torque in response to the error. 
Fixed Inputs and Outputs 
These parameters are not viewable on the keypad, They are accessible using the DSE 890 Configuration Tool. 
Speed Demand 
This is connected to the output of the REFERENCE function block. 
Speed Feedback 
The speed feedback is derived from the encoder when the Control Mode is configured as CLOSED-LOOP VEC. When 
configured as SENSORLESS VEC the speed feedback is calculated from the voltages and currents slowing in the motor, and 
the motor model. 
Torque Demand 
The output of the SPEED LOOP function block is a torque demand. This torque demand is passed on to the TORQUE LIMIT 
function block. 
Parameter Descriptions 
SPEED PROP GAIN 
PREF: 78.01  Default: 20.0  Range: 0.0 to 3000.0 
Sets the proportional gain of the loop. 
Speed error (revolutions per second) x proportional gain = torque percent. 
SPEED INT TIME 
PREF: 78.02  Default: 100 ms  Range:      1 to  15000 ms 
This is the integral time constant of the speed loop. A speed error which causes the proportional term to produce a torque 
demand T, will cause the integral term to also ramp up to a torque demand T after a time equal to “speed int time”.