Fluid Components International MT86_MT86HT Manual Installation - Manual (Page 6)

FLUID COMPONENTS INTL CHAPTER 2 - INSTALLATION
Models MT86, MT86HT 2 - 6 Doc. No. 003162 Rev. F
Input Power
Warning: The output terminals are not power isolated with use of 24 Vdc as a power source.
Note: Before inserting the cable core into the terminal strip connector, first turn the terminal screws 10 turns
counterclockwise. If this is not done, there is a possibility of inserting the wires between the top half of
the clamps and the frames instead of between the two clamp segments.
FCI strongly recommends installing an AC line disconnect switch (and possibly a fuse) between the power source
and the flowmeter. The line switch is an easy way to remove power for calibration and maintenance procedures.
Also the line switch is an added safety feature.
100 Vac, 115 Vac, 230 Vac or 24 Vdc is the power source for the flowmeter (use only one power source). Wire the
power directly to the power supply terminal strip TS1.
Isolated Output Option and 4-20 mA Adjustment
An isolated 4 to 20 milliampere (mA) output is an available option. The isolated output is available by connecting a
loop powered isolator module to the transmitter output. Figure 2-9 shows the isolator output module. The module
has its own set of output terminals which provide an isolated 4 to 20mA output equal to the non-isolated instrument
output. This one-to-one current isolation is used to prevent instrumentation ground loops. See Figures 2-10 or 2-11
for the appropriate wiring diagram to install the isolated output module.
Use of the isolator module will add a small signal conversion error to the instrument output and limit the output load
to 350 ohms. The module must be adjusted in the field to the specific customer load. A red LED on the module
indicates when loop power is applied.
1. Connect the customer load with a milliampere meter in series with the output terminals of the isolators. Observe
the correct wiring polarity.
2. Connect a milliampere meter in series with the input terminals. Observe the correct wiring polarity.
3. Apply power to the instrument. Initiate a full process media flow. Allow a 10 minute warm-up period.
4. Adjust the isolator output span potentiometer (see Figure 2-3 for placement) so both of the milliampere meters
read the same.
5. This completes the output isolator setup. Turn off the power, remove the milliampere meters and reconnect the
wiring.
Figure 2-3. Isolator Output Module
Installation Quick-Check List
1. Verify that serial numbers match.
2. Be sure the FLAT and FLOW ARROW are properly oriented.
3. Insure there are no leaks at the process connection.
4. Verify that the wiring is properly connected per the wiring diagram.