Yamatake Corporation
ST3000 Smart Transmitter Series 900 Electronic Differential Pressure/Pressure Transmitter
4-9
4-3 : Piping ST3000 Smart Transmitter
Summary
The actual piping arrangement will vary depending upon the process measurement
requirements and the transmitter model. Except for flanged and remote diaphragm seal
connections, process connections are made to 1/4 inch or 1/2 inch NPT female connec-
tions in the process head of the transmitter’s meter body. For example, a differential
pressure transmitter comes with double ended process heads with 1/4 inch NPT con-
nections but they can be modified to accept 1/2 inch NPT through optional flange
adapters.
The most common type of pipe used is 1/2 inch schedule 80 steel pipe.
Many piping arrangements use a three-valve manifold to connect the process piping to
the transmitter. A manifold makes it easy to install and remove a transmitter without
interrupting the process. It also accommodates the installation of blow-down valves to
clear debris from pressure lines to the transmitter.
Figure 4-7 shows a diagram of a typical piping arrangement using a three-valve mani-
fold and blow-down lines for a differential pressure transmitter being used to measure
flow.
Figure 4-7 Typical 3-Valve Manifold and Blow-Down Piping Arrangement.
Process connections
Table describes typical process connections for a given type of transmitter.
To High Pressure
Side of Transmitter
To Low Pressure
Side of Transmitter
Drain
Valve
Drain
Valve
3-Valve
Manifold
To Waste
To Waste
To Downstream Tap
To Upstream Tap
