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Symptoms
Diagnostics
Cause
Remedy
Flow not stable, and/or a flashing
"F" is displayed continuously/occa‐
sionally
• Error "Measure‐
ment path error" is
pending (menu 2.1)
• Gain (menus
6.5.1.X) for the ac‐
tive paths > 250
• TOF (menus
6.5.5.X and
6.5.6.X) for the ac‐
tive paths is not sta‐
ble
• Error counters (me‐
nus 6.5.4.X) are not
equal to 0.
Air bubbles or particles
of any kind disturbing
the measurement
Make sure that the pipe line is venti‐
lated and that the concentration of
particles is limited to a level at which
normal measurement with the meter
is possible.
Cable partly connected
Make sure that the transducer cables
are connected in the transmitter and
in the sensors (SONO 3200 or SONO
3300).
Check the connection of the cable
screening.
Make sure that the screen and center
pin is connected inside the transduc‐
er top.
Ultrasonic echoes
Make sure that the entered path
lengths correspond to the measure‐
ment report.
Device displays negative flow, and/
or a flashing "F" is displayed con‐
tinuously/occasionally
-
Transducer cables incor‐
rectly connected
Make sure that the transducer cables
are connected correctly:
1A → 1A
1B → 1B
2A → 2A
2B → 2B
Wrong setting of meas‐
urement direction
Make sure that the setting of menu
3.1.5.1 is "+ Direction"
Pulse/frequency output does not
work, and/or a flashing "F" is dis‐
played continuously/occasionally
Error "P/F too high" is
pending (menu 2.1)
Internal electrical failure
(open circuit, short cir‐
cuit etc.)
Start simulation on the pulse/
frequency output via menu 2.4. The
frequency measuring instrument is
coupled directly on the terminals.
Pulse/pause or frequen‐
cy out of range
Adjust pulse or frequency output set‐
tings (menu 4.2)
Device displays 0 flow.
Device status: "OK"
Process flow value is
very low compared with
the low flow cut off limit
of the device
For testing, check the low flow cut off
(menu 3.1.6) is set to 0.
LCD display dark or partly dark
(missing characters)
Internal electrical failure
(open circuit, short cir‐
cuit etc.)
Turn off power. Check the connec‐
tions for the power supply PCBA and
the flat cable for the display module.
Start display test (menu 2.3.2.) in
case of partly dark display.
Operation with infrared keys not
possible
Light interference
Check that display is not dirty.
Check that display lid is locked (PDM
force control).
Bright auxiliary tools may be of assis‐
tance.
Troubleshooting/FAQs
9.1 Eliminating process errors
SITRANS FUS060 with PROFIBUS PA
76
Operating Instructions, 09/2021, A5E02225054-AD