NEMA 4X instrument Front
531 - Automatic PID backup of critical loops
532 - Automatic manual backup of critical loops
Not a point of failure!
Full indication and alarm capability
Available in new Field Mount case



CPI has taken a step ahead in the control world by providing a simple and cost effective way to provide automatic PID or Auto/Manual backup control of critical loops controlled by PLC, DCS, or PC systems. Not a point of failure, CPI offers a wide range of programmable functions to tailor the response to lost or returning host signal to your application's specific needs.
The  531 provides automatic PID control backup of your critical loops. The host 4-20 mA control signal passes through the 531 without degradation. Upon loss of the control signal, the 531 resumes PID control based on the last known good control signal. Upon control signal return, the 531 will provide a bumpless transfer from the existing signal to the new control signal. As an alternative, the return to the HOST control signal can be programmed to take place only by operator intervention. This allows verification of the control signal's propriety.
The 532 Auto/Manual station also detects lost signal but substitutes a fixed signal based on the last known good control signal or a preset control signal. The operator may then manually adjust the Auto/Manual station's output. The return of the HOSTS control signal is handle in the same manner as the 531. 
CPI now offers cost effective protection from system failure