Parker 690+ series - ZERO SPEED

Programming Your Application 1-135
690+ Series Frequency Inverter
ZERO SPEED
This function block detects when the speed
is at or close to zero. HYSTERESIS and
THRESHOLD are user-definable.
Functional Description
true zero
THRESHOLD
speed demand
AT ZERO SPD DMD
0.5%
0.3%
0.7%
HYSTERESIS
window
Example where BAND = 0.2%
AT ZERO SPD FBK
AT STANDSTILL
speed feedback
Off level
On level
Zero Speed
–
AT ZERO SPD FBK [1233]
–
TRUE
–
AT ZERO SPD DMD [360]
–
TRUE
–
AT STANDSTILL [1234]
–
TRUE
0.10 %
–
[359] HYSTERESIS
–
0.50 %
–
[357] THRESHOLD
–
MMI Menu Map
1
SETUP
2
SETPOINT FUNCS
3
ZERO SPEED
HYSTERESIS
THRESHOLD
AT ZERO SPD FBK
AT ZERO SPD DMD
AT STANDSTILL
Parameter Descriptions
HYSTERISIS
Range: 0.00 to 300.00 %
Provides a hysteresis band about which the outputs are stable.
IF the hysteresis value is >= to the Threshold
THEN the level is set to 2 x the hysteresis value and the Off level is set to zero,
ELSE the On level = Threshold + Hysteresis and the Off level = Threshold - Hysteresis.
THRESHOLD
Range: 0.00 to 300.00 %
The nominal level below which the outputs are set.
AT ZERO SPD FBK
Range: FALSE / TRUE
Speed feedback. TRUE when at zero speed feedback, as defined by THRESHOLD and
HYSTERESIS.
IF (abs(speed feedback)) > On Level at zero speed = FALSE
ELSE if (abs(speed feedback)) <= Off Level at zero speed = TRUE
ELSE at zero speed is unchanged
AT ZERO SPD DMD
Range: FALSE / TRUE
Speed demand. TRUE when at zero speed demand, as defined by THRESHOLD and
HYSTERESIS.
AT STANDSTILL
Range: FALSE / TRUE
TRUE when both AT ZERO SPD FBK and AT ZERO SPD DMD are TRUE.