PID Symbol for Emergency Stops 1

[swartzmech]

Has anyone placed emergency stop buttons (with signal back to dcs)on their P&ID's for motor control, next to an HOA? Would you use something for the symbol identification like XSC for a user defined control switch?

 

[JLSeagull]

HS is common for hand switch. If used I would write ESD, Trip, or a similar description in the upper right of the bubble.

 

[typhonic]

Perhaps this should be a separate thread, but your question got me thinking - we receive P&IDs with E-Stop shown as a function inside the DCS, that is, a pick on the screen that should stop a process immediately. I know I prefer to have only hardwired switches using the name "E-stop," but I wonder if there is a code requirement to back up my preference.

...John