ARI Armaturen ARImetec-S EN - Manual (Page 28)

Page 2-28 Rev. 0040807015 1014
Operating Instructions
ARImetec
®
-S
As shown in the diagram above, the temperature sensor should if possible be positioned on
a flat surface at the steam trap inlet "T
0
(inlet)". The connected ultrasonic sensor should be
fitted vertically with gentle pressure onto the housing or onto the hood, cap or cover:
- Stable ultrasonic value below the limit curve:
If a stable ultrasonic value is measured and can be plotted below the limit curve shown
here, the steam trap is steam-tight. By taking a temperature measurement (refer to the
note on temperature measurement), you can determine whether the steam trap is
operating at the normal working temperature:
If a thermostatic (bimetallic, balanced pressure or thermodynamic) steam trap is
functioning correctly, the working temperature T
(internal)
should be between 5 and 30 K
less than the boiling temperature, depending on the type, or approximately equal to the
boiling temperature in the case of float-type steam traps. If the temperature is
significantly more than 30 K below the boiling temperature, either the sub-cooling setting
of the steam trap is too high or the steam trap is blocked or defective (assuming the
system is operating).
- Periodically fluctuating ultrasonic value:
Periodic fluctuation of the ultrasonic reading between a maximum and minimum value
indicates intermittent operation of the steam trap. The steam trap is opening and closing,
in other words it is functioning correctly.
Once again, the working temperature T
(internal)
of a thermostatic (bimetallic, balanced
pressure or thermodynamic) steam trap should be between 5 and 30 K less than the
boiling temperature, depending on the type, or approximately equal to the boiling
temperature in the case of float-type steam traps.
- Stable ultrasonic value above the limit curve:
If the value is above the limit curve, the steam trap must be isolated from other sound
sources to confirm that the ultrasonic signal is only being produced by the steam trap
under test. This can be verified by taking an ultrasonic reading on the pipe upstream and
downstream of the steam trap.
If the ultrasonic readings at the steam trap are higher than at the pipe, ultrasound is
being produced by a flow in the steam trap. If the ultrasonic readings at the steam trap
CONA
®
S / SC
Ultrasonic measurement
T
O
(inlet)
T
O
(outlet)
T
O
(outlet)
Temperature measurement
Temperature measurement