ASCII - Command ROFFS    
Syntax Transmit ROFFS [Data]    
Syntax Receive ROFFS   Available in  
Type Variable rw   MMI Yes
ASCII Format Integer32   CANBus Object Number 35E7 (hex)
DIM m   PROFIBUS PNU 1831 (dec) IND = 1 (dec)
Range long int   DPR 231 (dec)
Default 0    
Opmode 8   Data Type Bus/DPR Integer32
Drive State -   Weighting  
Start Firmware 1.20    
Configuration No   Last Change of this Object 1.3
Function Group Position Controller   EEPROM Yes
Short Description Reference Offset

Description

The ROFFS parameter can have various functions, depending on the type of position sensor that is used for the position control loop.

1. Resolver or single-turn encoder (homing to reference point is possible)
The ROFFS parameter can be used to assign a freely chosen absolute position as the reference position (zero position) that will be reached at the end of a homing movement.
The scaling of the position depends on the settings for PGEARI, PGEARO, PRBASE.
If the resolution is set to 1 (PGEARI=PGEARO), then internal units (counts) will be used.

2. Absolute encoder (multi-turn, homing to reference point is also possible)
If the position value of the absolute encoder is to be altered, this can be done with the help of the ROFFS variable. When the amplifier is switched on, the value of the ROFFS variable is added once to the position value of the absolute encoder. Since this correction is only made when the amplifier is switched on, the parameter value must be saved in the EEPROM (using the SAVE command) after every alteration of the ROFFS variable, and the amplifier must then be switched off and on again (COLDSTART command).

Example:
If a position 10000 is shown when the amplifier is switched on, with ROFFS=0, then entering ROFFS 10000 will shift the position to the value 0.