HEIDENHAIN PWM 20 - Manual (Page 24)

August 2014 Overview of cables and adapters 25
3.2.2 SA 110 service adapter (online diagnosis) for floating feed-through operation (listening-in)
The SA 110 Service Adapter serves to connect the PWM 20 and the IK 215 into the measuring
circuit of the machine axis ("closed loop"); data transfer is purely serial (no incremental signals).
Using the SA 110 allows for controlled traverse of the machine axis during measurement.
The diag output of the SA is connected to the input (IN) of the PWM 20 (or of the interface card
IK 215 IN). The data transfer between the encoder and the subsequent electronics can be
observed via optocouplers (inactive listening-in).
Note
The following absolute interfaces allow for closed-loop operation:
- EnDat 2.2 (purely serial, no incremental signals)
- Fanuc
- Mitsubishi as of version 02 (with PWM 20 only)
The TNC must support the diagnostic function.
If an SA is connected into the measuring circuit, the ATS software no longer can
actively intervene in data transfer (control/encoder) to delete errors and warnings,
etc.
The supply voltage must be provided by the PWM 20; do not activate "Use power
supply from subsequent electronics"!
The data transfer can only be listened in (monitored)!
For more information, refer to the section “Feed-through operation (listening-in)" on
page 21.