Onicon FT-3500 - FT-3500 Troubleshooting Guide

FT
-
3500 ELECTROMAGNETIC FLOW METER
ONICON Incorporated 727.447.6140 Page 55 onicon.com
5.5 TROUBLESHOOTING GUIDE
NOTE: Also refer to the START-UP AND COMMISSIONING GUIDE located on page 46/47.
REPORTED PROBLEM POSSIBLE SOLUTIONS
No signal • Verify that the meter is properly inserted into the pipe.
• Verify that the remote sensor ow arrow points in the direction of ow in the pipe.
• Verify 24 V supply voltage.
• Verify correct wiring to control system (see wiring diagram).
• Verify that there is ow in the pipe.
• Verify that the meter earth cable is connected to earth.
• Low conductivity water (≤ 20 µsiemens) may activate the empty pipe detector and/
or increase the potential for electrical noise problems.
Reading is too high or low • Verify pipe size. Contact ONICON if pipe size is dierent from calibration tag.
• Verify that the meter is properly inserted into the pipe.
• Verify that the remote sensor ow arrow points in the direction of ow in the pipe.
• Verify correct wiring to control system (see wiring diagram).
• Conrm that the output signals are consistent with each other (frequency vs.
analog, etc).
• Conrm that the control system is programmed for correct ow range or scale
factor.
• Verify that the meter earth cable is connected to earth. A poor earth connection
can lead to excessive noise that can aect the ow reading.
Analog signal seems
high or low and does not
correspond to frequency
output
• Verify Analog Out Max and Flow at MaxFreq
• Check for ground loop or oset voltage:
• Disconnect analog signal input from control system and measure analog output
directly from the ow meter. Reconnect signal input to control system and
measure the analog signals again. Any dierence between these readings indicates
a potential ground loop or oset voltage. Please contact ONICON for further
assistance.
Control system displays
ow rate, but no ow rate
is indicated on the local
display module or Btu
meter
• Verify that all wires from the ow meter are connected to the display module or Btu
meter.
• The frequency output wires (green and yellow) must be connected for any ONICON
display or Btu meter.