Siemens SIMATIC FM 351 Manual page 73

Address Name
44.0 REFPT
Incremental encoder:
You require the reference point coordinate for the "reference point approach" mode.
If the axis is not synchronized after writing and activating machine data, the actual value is set to the
value of the reference point coordinate.
Absolute encoder (SSI)
You require the reference point coordinate for the mechanical adjustment of the encoder.
Read the description of absolute encoder adjustment in Section 8.6 (page 8-19), explaining the
interaction of absolute encoder adjustment with other data.
The value of the reference point coordinate must be within the working range:
Linear axis
including the software limit switches
Rotary axis
Greater than or equal to 0 and less than the value "end of the rotary axis" (0
coordinate < "end of the rotary axis").
Address Name
52.0 REFPT_TYPE
With type of reference point approach, you select the conditions for synchronization of the axis.
The first statement defines the start direction in which the reference point approach starts.
The second statement defines the location of the zero marker that leads to synchronization relative to
the reference point switch.
Use of this data is described in Section 9.3 (page 9-11).
Address Name
99.0 REFPT_SPD
With this data you select the speed for the start of a reference point approach:
FM 351 Positioning Module
C79000-G7076-C351-02
Data Initial Value
Type
DINT L#0
Data Initial Value
Type
DINT L#0
Data Initial Value
Type
BOOL TRUE
Machine Data and Incremental Dimensions
Description
Reference point coordinate:
Range:
–1 000 000 000 m to 1 000 000 000 m at
a resolution of 1 m/pulse
–100 000 000 m to 100 000 000 m
at a resolution of < 1 m/pulse
Description
Type of reference point approach:
Ranges:
0 = plus, ref. point switch in direction +
1 = plus, ref. point switch in direction –
2 = minus, ref. point switch in direction +
3 = minus, ref. point switch in direction –
Description
Start speed for reference point approach
0 = rapid speed
1 = creep speed
reference point
8-13