Kamstrup MULTICAL 41 Installation Manual page 4

3. Mounting of flow part
Before mounting the flow part (flow sensor), flush the system
thoroughly and remove protection plugs/plastic membranes
from the flow sensor.
The flow direction is indicated by an arrow on the side of the
flow sensor.
There are no requirements for straight inlet, but we recommend
a straight inlet of 3...5 × DN.
To prevent cavitation the operating pressure at the flow sensor
must be min. 1.5 bar at Q3 and min. 2.5 bar at Q4.
The flow sensor must not be exposed to pressures below
ambient pressures (vacuum).