Programmable Threshold Set-Up - Control Techniques Commander SE Advanced User's Manual

12.19

Programmable threshold set-up

The Commander SE drive software supports a software controllable numerical comparator. This comparator can be used to
detect when an internal or external signal exceeds a user set point threshold. The threshold comparator also provides a
hysteresis band to prevent erratic operation at or near the threshold point.
This example shows how the programmable threshold can be set up to switch on an integrated motor cooling fan, when the
drive speed falls below 50%.
Parameter set-up
12.03 = 5.01 Threshold detector source parameter assigned to motor frequency.
12.04 = 50% Threshold level as a percentage of maximum reference.
8.27 = 12.01 Programmable relay source parameter assigned to "threshold exceeded" signal.
Set threshold detector hysteresis band (12.05) if required. This will define the band within which no change will occur on
the output.
Perform a Save routine: xx.00 = 1000 and press red Stop / Reset button on drive.
Commander SE Advanced User Guide
Issue Number: 4
SPEED REFERENCE
100%
Motor ventilation OFF
50%
Motor ventilation ON
0%
15 16
1 2 3
U V W
240V AC
Fan Supply
Contactor
179