Appendix C. Temperature Transmitter Installation
Transport® Model PT878 Portable Liquid Flowmeter User’s Manual 243
Appendix C. Temperature Transmitter Installation
The PT878 requires a supply and return temperature input to measure
energy rate and consumption. You must connect the temperature sensors to
a 4 to 20 mA transmitter (powered by the PT878 or externally) and then
from the transmitter to the PT878 (a special GE cable is required to make
transmitter-to-PT878 connections).
The factory can supply the Resistive Temperature Device (RTD) and a Dual
Transmitter (DTR) or you may supply your own. If you supply your own
equipment, you will need to order a special GE cable with a LEMO
connector to make connections from the transmitter to the PT878.
To install the RTDs, you need to do the following:
•find a suitable installation site
•mount RTDs on the pipe
•make electrical connections
Use the instructions that follow to install the RTDs.
C.1 Guidelines for RTD Installation
You should have discussed possible installation sites with an applications
engineer or field sales person by the time you receive the RTDs. However,
you should follow these guidelines to ensure accurate temperature
measurement:
•Do not install the RTD on a pipe seam.
•Clean the pipe at the installation location.
•Do not install the RTD on the top or the bottom of the pipe.
•Apply thermal couplant to the RTD before mounting it to the pipe.
•Insulate the pipe and RTD after installation.
If you have a GE RTD, use the instructions in the next section to properly
mount the RTD on the pipe.