Actual Value Feedback - Lenze 4800 Manual

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7.4 Additional control functions
7.4.1 Redundant actual value feedback
Purpose
In the event of a failure of the actual speed encoder like tacho, resolver or
incremental encoder, this function enables to decelerate the DC drive standstill in
a controlled way (emergency operation) without being inhibited by a TRIP.
Function
If the actual value encoder fails, it is changed to armature voltage feedback:
( Speed operation with configuration C005 = -1X-,
( Torque control with configuration C005 = -4X-,
( Dig. frequency operation with the configurations C005 = -5X-, -6X-, -7X-,
The set-value channel remains active, i.e. a possibly selected phase control is not
active.
Warning!
The message "encoder polarity reversed" does not automatically lead to a change
of the actual value encoder to armature voltage control.
With the change to armature voltage control, the feedback resolution becomes
less compared to a tacho or resolver. Furthermore, faults in speed adjustment
(encoder constant) can occur.
Change to configuration C005 = -10-.
Change to configuration C005 = -40-.
Change to configuration C005 = -10-.
Configuration
48XX/49XXSHB0399
7-55