Fluid Components International MT86_MT86HT Manual Troubleshooting - Manual (Page 11)

Doc. No. 003162 Rev. F 5 - 11 Models MT86, MT86HT
CHAPTER 5 - TROUBLESHOOTING FLUID COMPONENTS INTL
Switch Point Calibration Procedure
The flowmeter has field adjustable switch point relays. Relay energization is changed by moving a plug-jumper on
the circuit board. Each switch point circuit has an LED which indicates the relative condition of the flow signal. In
all cases, the LED is illuminated when the flow signal is below the set point. Jumper positions J1 and J2 select the
energization state of the switch point relay number 1 (K1). With J1 in place, the relay is energized when the signal is
above the set point. With J2 in place, the relay is energized when the signal is below the set point.
1. Connect an appropriate meter to TP13 and TP5 on the main circuit board.
2. Set the calibration switch (SW4) on the main circuit board to the CAL position. See Figure 5-2.
3. Adjust the CAL potentiometer (R23) on the main circuit board until the meter readout shows the desired switch
point signal level (select the desired signal level form the calibration table).
4. If the red LED is lit, turn potentiometer R3 counterclockwise until the LED turns off. With the LED off, turn R3
very slowly clockwise, just until the LED turns on, then stop.
5. Vary the set point by turning the potentiometer (R23) clockwise and counterclockwise through the set point to
see that the relay changes at the desired point.
6. Remove the meter from the test points. Seal the adjusted potentiometer (R3).
7. Set the calibration test switch to OP, the operate position.
Switch Point Verification Procedure
Note: Switch point relay boards can be located on any of the output buss connectors P7 through P9 and P11.
All switch points are totally independent of each other and may be set to actuate at any flow signal.
1. Connect an appropriate meter to TP13 and TP5 on the main circuit board.
2. Set the calibration switch (SW4) on the main circuit board to the CAL position. See Figure 5-2.
3. Adjust the CAL potentiometer (R23) on the main circuit board until the test signal level passes through the
switch point setting. Observe the LED to determine exactly where the set point is.
4. If the red LED is lit, within 2% of the full-scale signal range, the set point is properly adjusted. If the set point is
out of tolerance, go the switch point calibration procedure above. If the set point is within tolerance go to the
next step.
5. Remove the meter from the test points.
6. Set the calibration test switch to OP, the operate position.
Analog Output Test Procedure
To verify operation of the output modules and related circuitry, a convenient test signal is applied to the analog
output. Use this test signal to sweep through the full signal range (0-10 Vdc) and observe operation of the output
modules and customer interface circuitry.
1. Place switch SW4 in the CAL (CALibrate) position.
2. Connect a DMM between test point TP13(+) and TP5(-) signal ground.
3. Potentiometer R23 adjusts the test signal level through the full scale 0-10 Vdc operating range.
4. Observe the operation of the output modules and the customer interface circuitry.
5. When the testing is complete, return the switch SW4 to the OP (OPerate) position.