Replace old Siemens Positioner feedback


Thread Starter


We're about to revamp a power plant that was built in the late 60's. One of the problems I'm facing is to get the position of a bunch of steam valves in to the new PLC. The valve positioners are from Siemens and have some magic device for position feedback with this data:

Excitation Voltage: 24V
Frequency: 50Hz
Excitation Current: 0.6 A
Internal resistance: 25 Ohm
The spec says the feedback is inductive.

<b>Any ideas how to convert this to 4..20mA or 0-10V ?!
If anyone knows this old Siemens stuff, the valve positioner is of type ZR-AN15 and the feedback is of type ZR-GS01.

..and - No, we will not replace the Valve positioners, that's way too expensive for this project.