4
SITRANS F C MASSFLO
®
®
®
®
®
mass flowmeter type MASS 2100, DI 3 - DI 40
Direction of flow
Static back pressure
Static back pressure
The arrow on the sensor indicates the direction of flow defined as “positive” (the meter is able to
measure flow in both directions).
As far as possible, the liquid should flow in the direction of the arrow (on the sensor) to avoid partial
emptying of the sensor, especially with low flow.
In addition there should be a valve (check/solenoid) that closes when the flow is zero so that the
liquid does not flow back and causes partial emptying of the sensor.
Valve
Reverse
Inverse
Forward
Valve
Location
The flowmeter can be located both indoors and outdoors, but the following conditions must be
observed:
Liquid temperature:
−
50 to +180
°
C.
Ambient temperature, operation:
−
20 to +55
°
C.
When the temperature difference between a liquid and the surroundings is large, the sensor must
be insulated to prevent 2-phase flow and the resulting measuring inaccuracy. This applies
especially in the case of low flow.
Important!
The sensor must
always
be completely filled with a homogeneous liquid in single phase,
otherwise measuring errors will occur.
If there is air/gas in the liquid or liquids which are volatile, horizontal sensor mounting is
recommended.
Version
Compact IP 67
Separate
Compact Ex-d
Horizontal mounting in
pipe
Mount the sensor on a vibration-free wall or steel frame as shown.
Ensure that the sensor is not emptied of liquid (during normal operation) otherwise incorrect
measurement will occur.
Locate the sensor low in the pipe system in order to avoid under-pressure in the sensor and
consequent air separation in the liquid.
If the flowmeter is mounted horizontally, it is self-emptying.
With low flow, horizontal mounting is recommended, in this way air bubbles are easier to
remove.