I have an existing orifice plate with direct mounted dp flow transmitter and I'm planning to purchase additional DP flow transmitter that will also be connected to the existing plate for the shutdown system. What will be the best installation of this new DP transmitter? Considering that this will be remotely mounted using impulse line.

 

Depends on the criticality of your emergency criteria.

Most operating plants typically require trip conditions rely on a separate measurement altogether such as a flow actuated switch, etc. so-called process interlock conditions are performed using a alarm which either hardwired or in your DCS. Multiple transmitters are used when transmitter reliability is a concern, but then you have to concern yourself with protection against common mode failures...

Hardly a question that can be full addressed in a forum.