Experimental Physics and
Industrial Control System

Mortaza

 

At the Australian Synchrotron we have the following:-

 

Injection and Storage

EPICS can read PSS status via modbus TCP/IP. IOC can only be on one specific TCP/IP address.

PSS uses Pilz PLCs with the concept of “Standard” and  “Fail Safe” sections (Similar concepts to Siemens and Rockwell etc.). EPICS can only read the “Standard” PLC memory that is written to from the Fail Safe section.

 

Beam lines

Same as above with the added ability for IOC to send open and close shutter “REQUESTS”

These are integer based transactions (from the PLCs view) where “0” means “do nothing” to prevent an IOC restart altering the state of the plant

The standard section checks the validity of the REQUEST, blocking more than one REQUEST at a time. To request a shutter to open it must closed, to request a shutter to close it must be open (i.e. ignore REQUESTS while a shutter is moving). Ignore open and close REQUEST at the same time. Once the “Standard” section has process the “REQUEST” the modbus register that EPICS writes to is cleared to 0.

Finally one the “Standard” section is happy that the REQUEST is valid it is passed to the “Fail Safe” section via a narrow set of shared memory.

 

Here is the key, IOC can only send a REQUEST to open/close a shutter. The “Fail Safe” section then checks all related permits to determine if the REQUST will be actioned or ignored. EPICS plays no part in any safety instrumented loops on the PSS.

 

Hope this is of some use

 

Bryce Karnaghan

 

 

Subject: From: To:

EPICS for personal safety system [email protected] [email protected]

 

Hello everyone,

 

We are planning to build a monitoring system for our PSS (personal safety system) in SESAME based on EPICS.

I am looking for some advice if it is recommended that the IOC has writing permission to PSS PLCs or it should be the case of the IOC only reading from PSS PLC.

 

Many thanks for your help in advance.

 

Morteza Mansouri

PSS (Personal Safety System) Engineer

SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East)

P.O. Box 7, Allan 19252, Jordan

Tel: (+962-5) 3511348 , ext. 289

Fax: (+962-5) 3511423

Mob: (+962-7)95075323

www.sesame.org.jo

[email protected]

[email protected]