Many process operations have processes that require tight pressure control. Some processes are too critical to rely on just one pressure transmitter, since a transmitter failure could cause a nuisance or spurious trip or process upset. Furthermore, not all of these situations are in close proximity to a DCS.
Instead of considering a sophisticated PLC and additional pressure transmitters, consider utilizing a 2oo3 voting scheme with SPA2 Site Programmable Alarm Trips by wiring their relays in a shutdown or alarm circuit scheme. It is very easy to program vs a PLC and its SPDT relays are rated at 5A 250VAC/24DC. The SPA2 is approved for installation in Class I Div 2/Zone 2 locations and is push button or PC programmable with quick and easy to use menus. Each SPA2 has a local display and an optional 4-20mA retransmission.
Key attributes:
- Simple 2oo3 voting configuration
- Easy programming
- Class I Div 2/Zone 2 approval and local display