The gage mechanism is enclosed in a polycarbonate, break-resistant case and lens. A polished stainless steel bezel and O-ring seals help protect this rugged instrument from the external environment. Accuracy and protection from moderate overpressure is assured by a unique, unitized diaphragm chamber. A built-in pulsation dampener helps eliminate pointer flutter and is removable for cleaning. Inside the A25DP-30, the tempered nickel silver gage pointer acts as a pressure indicator and as one switch pole which completes a circuit when it touches the adjustable limit contact. Contacts have a self-cleaning motion to ensure electrical continuity.
The A25DP-30 features a beryllium copper diaphragm sensing element and a 1/8-27 NPTM brass process connection. The adjustable limit contact is an SPST contact; pilot-duty only, 2A @ 30 VAC/DC; closed when the low limit is met, and open when the pointer is in normal operating range.