What is the need for main fold valves with a DP gauge transmitter

Why do we need to install such type of manifold with DP Gauge transmitter?


For safety and to isolate the fluid we use the manifold valves. Manifold valves are used for isolation and equalizing of the process to the transmitter diaphragm. For maintenance purpose, While commissioning or isolating, if the manifold is not there, either side will act overpressure resulting in diaphragm weakening and the over flow range