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6-74
Programming Your Application
590+ Series DC Digital Converter
SPEED LOOP
Functional Description
Speed Loop PI Output
The PI output is accessible via Tag No. 356. This point is before the I Limit clamps and the
summing of the additional current demand.
This Tag is not visible on the MMI.
Speed Loop PI with Current Demand Isolate
The speed loop output is still valid (active) with the I DMD. ISOLATE parameter enabled.
Note:
1
The speed loop is reset by unquenching the speed loop/current loop.
2
I DMD. ISOLATE is overridden by Program Stop (B8) or Normal Stop (C3).
3
The speed loop PI is holding the integral term as soon as the PI output reaches
current limit. This is true even in Current Demand Isolate mode where it may
interfere depending on the way the speed PI is used. This feature is currently not
suppressible.
105% Speed Demands
The speed demand clamping allows the speed setpoint to reach 105%. This applies only to the
final summing junction immediately before the speed loop and also to the Setpoint Sum 1
output. Individual speed setpoints are still clamped to 100%.
Parameter
Tag
Range
PRESET TORQUE
595
-200.00 to 200.00 %
The PRESET TORQUE is pre-loaded into the speed loop integral store as the speed loop in
enabled. This is scaled by PRESET T SCALE.
This may be used to pre-load the output of the speed loop in elevator/hoist applications to
prevent the load from falling back when the brake is released. PRESET T SCALE may be
used in situations where the load may vary.
PRESET T SCALE
604
-200.00 to 200.00 %
Scaler for PRESET TORQUE.