NORD Drivesystems BU0210 - Manual (Page 20)

SK 2x5E with "PosiCon Functionality"
20 Subject to technical amendments BU 0210 GB
3.2.3 Encoder monitoring
If an absolute and an incremental encoder are present, the positioning difference between the two encoders
can be monitored with parameter P631 "Slip Error Abs/Inc". The maximum permissible deviation between the
absolute and the incremental encoder is specified by the value set in this parameter. With the value "0" slip
error monitoring is disabled. If the maximum permissible deviation is exceeded the error message "E013
(E14.6)" is activated. The gear ratio or the positions where the two encoders are installed may differ. For each
of the two encoders a parameter value for P607 "Speed Ratio", P608 "Reduction Ratio" and P609 "Offset
Position" can be set.
If there is no second, redundant encoder for position monitoring a slip error for the position can be specified via
the parameter P630 "Pos. Slip Error". In this case the current position is compared with the change in position
calculated from the current speed. On reaching a target position, the estimated position is set to the actual
position value of the encoder in order to prevent addition of errors over time. If the positioning difference
exceeds the slip error value set in P630 "Pos. Slip Error", the error message "Error E013 (E14.5)" is activated.
For larger travel paths larger values are necessary in P630. The necessary value is best determined by
experiment. With the value "0" slip error monitoring is disabled.
The permissible operating range can be restricted with the parameters P616 "Minimum Position" and P615
"Maximum Position". If the drive unit departs from the permissible range, the error message "Error E013
(E14.7) maximum position exceeded" or "Error E013 (E14.8) minimum position undershot" is activated.
With a set value of "0" the relevant position monitoring is disabled. In parameter P604 "Encoder Type", setting
3, 4, 5 or 7 the position monitoring is also not enabled.
ATTENTION
Position setpoint values which are greater than the set value for "Minimum Position" in parameter
P616 and "Maximum Position" in parameter P615 will be internally limited to these set values in the
inverter.