Rosemount 8712C - Installation Check and Guide

Model 8712C/U/H Magnetic Flowmeter Transmitters
2-16
Installation Check
and Guide
Use this guide to check new installations of Rosemount magnetic
flowmeter systems that appear to malfunction.
Before You Begin
Be sure that power to your system is off before beginning these checks.
Transmitter
1. Check that the correct flowtube calibration number entered in the
software. The calibration number is listed on the flowtube
nameplate.
2. Check that the correct flowtube line size is entered in the
software. The line size value is listed on the flowtube nameplate.
3. Check that the analog range of the transmitter matches the
analog range in the control system.
4. Check that the forced analog output of the transmitter produces
the correct output at the control system.
Flowtube
1. For horizontal flow installations, ensure that the electrodes
remain covered by process fluid.
For vertical or inclined installations, ensure that the process
fluid is flowing up into the flowtube to keep the electrodes covered
by process fluid.
2. Ensure that the grounding straps on the flowtube are connected
to grounding rings, lining protectors, or the adjacent pipe flanges.
Improper grounding will cause erratic operation of the system.
Wiring
1. The signal wire and coil drive wire must be twisted shielded
cable. Rosemount Inc. recommends 20 AWG twisted shielded
cable for the electrodes and 14 AWG twisted shielded cable for
the coils.
2. The cable shield must be connected at both ends of the electrode
and coil drive cables. Connection of the shield at both ends is
absolutely necessary for proper operation.
3. The signal and coil drive wires must have their own cables.
4. The single conduit that houses both the signal and coil drive
cables should not contain any other wires.
Process Fluid
1. The process fluid conductivity should be 5 microhms per
centimeter minimum.
2. The process fluid must be free of air and gasses.
3. The flowtube should be full of process fluid.