Vacon 20, Complete User'S Manual

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vacon parameter descriptions
9
2. When the Opening frequency limit has been reached the Open delay (P4.15)
must also elapse. Note! The output frequency is held at the Open frequency
limit until this.
3. When the two previous conditions are reached. The brake will open if the
output current is higher than the current limit.(P4.19)
Notice that any of the previous conditions can be left out by setting their val-
ues to zero.
Time
Output Frequency
Actual
Reference
P Open Frequency Limit
P Open delay
External Brake
1 2
1
= Open frequency Limit reached
2
3
= Open delay elapsed
= Brake opens if External Brake:Current limit is exceeded.
3
Brake
closed
Brake open
Relay
closed
Relay open
Figure 9.13: Starting / opening sequence with external brake
Closing brake conditions:
There are 2 conditions for closing the brake again. It’s enough that one is true
for the brake to close.
1. If there is no run command active and output frequency goes below Close
frequency limit (P4.17) or Close frequency limit in reverse (P4.18), depend-
ing on direction of rotation.
OR
2. Output current has gone below Current limit.(P4.19)