Instructions for Use SS 20.260
Page 4
2 Application range
The
SCHMIDT
®
flow sensor SS 20.260
is designed for stationary
measurement of the flow velocity as well as the temperature of air and
gases under atmospheric pressure.
The sensor is based on the measuring principle of the thermal anemom-
eter and measures the mass flow of the measuring medium as flow ve-
locity which is output in a linear way as standard velocity
1
w
N
(unit: m/s),
based on standard conditions of 1013.25 hPa and 20 °C. Thus, the re-
sulting output signal is independent from the pressure and temperature
of the medium to be measured.
The
SCHMIDT® flow sensor SS 20.260
is designed for the use inside
closed rooms and is not suitable for outdoor use.
3 Mounting instructions
General information on handling
The
SS 20.260
is a precision instrument with high measuring sensitivity.
In spite of the robust construction of the sensor tip soiling of the inner
sensor elements can lead to distortion of measurement results (see also
chapter 8 Service information
). During procedures that could stimulate
soiling like transport, mounting or dismounting of the sensor it is recom-
mended to place the enclosed
SCHMIDT Technology
protective cap on
the sensor tip and remove it only during operation.
During processes with enhanced risks of soiling such as
transport or mounting the protective cap should be placed onto
the sensor tip.
General installation conditions
The sensor measures the flow speed correctly only in the direction given
on the housing and sensor head (arrow). Make sure that the sensor is
adjusted in flow direction; a tilting of up to ±3° is allowed
2
.
The sensor measures unidirectional and must be adjusted cor-
rectly relative to the flow direction.
A sensor mounted in opposite direction of the flow direction leads to
wrong measuring values (too high).
1
Equates to the real flow velocity under standard conditions
2
Measurement deviation < 1 %
!
!