Mounting and installation
42/14-36 EN
Thermal Mass Flowmeter FMT400-VTS, FMT400-VTCS (Sensyflow VT-S/VT-CS)
13
In confined spaces at the mounting location the outlet run length can be shortened to 3
×
D. The reduction of the
minimum inlet run length, however, will impact on the achievable accuracy. High repeatability of the measuring
value is still provided.
Under certain circumstances, special calibration can be performed for insufficient steadying lengths. For this
purpose and in individual cases, consult the DKD Calibration Department of ABB Automation Products GmbH
at Alzenau. An on-site adjustment is also possible, if reference flow values are precisely known, by entering a
calibration factor.
The specifications for the steadying sections relate to air and most other measurable gases.
IMPORTANT
For gases with extremely low density (hydrogen, helium) the steadying lengths must be doubled. If type 2
pipe components with integrated flow straighteners are used, then the steadying lengths specified for air
are sufficient.
Components that influence the flow (e. g. valves, shut-off fittings and similar components) should possibly be
mounted at the outlet run length, i. e. behind the measuring point.