ITABAR Flow Sensor Type
FTMD
Operating manual
- If the mA- signal have big bounce, the valves A
and B must be closed and the system must be
vented
again.
10. Preventive
Maintenance
ITABAR sensors are intensive to dirt and soil
build-up and therefore nearly maintenance-free.
However, if cleaning is required:
- remove the sensor
- flush completely
- hand clean with a soft wire brush
11. Trouble
shooting
If, after start-up of the ITABAR sensor, any
measuring errors accur, they may possibly be
corrected quite easily:
Error:
No differential pressure indication.
Correction:
Check whether all instrument valves to the
∆
p-transmitter are opened.
The valve E must be closed (only for zero).
Check the alignment of the sensor with the pipe.
The arrow on the sensor must point exactly in the
flow direction (downstream).
Note:
Two-Phase flow or alternating phase flow will
cause an erratic spiking signal. The ITABAR
sensors are head-measuring devices and will not
accurately measure two-phase flow.
ITABAR-Flow-Sensors for low pressure steam
have condensate pots in which the condensate
water line is 25mm higher than the flange
connection of the sensor is installed precise
horizontal.
That means that water column of static and
dynamic pressure side must have the same high to
guarantee zero differential pressure when steam is
not flowing.
The arrangment of higher condensate line than
sensor connection has been done to secure the exact
water column onto the d.p. transmitter.
During steam flow the steam will move into the
condensate pots and will condensate to water. The
water level above line 1 will flow back into the
sensor and change again into steam. The steam
pressure from dynamic and static connection is
pressing onto the water level and the difference at
these pressures will be transmitted into mA-signal
through the differential pressure transmitter.
Please note that 25mm deviation in the line of 1
will give 25mm WG differential pressure.
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