TECHNICAL DESCRIPTION MULTICAL® 21 & flowIQ® 2101 /..02 /..03
58
Kamstrup A/S •Technical Description • 5512-897_J1_GB • 06.2016
12.5
Signal Paths
12.5.1
Measuring sequences
During flow measuring, the water meter passes through a number of sequences, repeated at fixed
intervals. Deviations only occur when the meter is in test mode.
12.6
Flow limits
In the meter’s working range, from ‘minimum cut-off’ to saturation flow (called ‘maximum cut-off’) the
flow through the meter will be registered with an accuracy which reflects legal requirements/OIML R49.
If the flow exceeds maximum cut-off (se tables in section ‘
)
, the water meter registers a
constant flow (at ‘maximum cut-off’). In practice, the highest possible water flow through the meter will be
limited by the pressure in the installation, or by cavitation due to too low downstream pressure.
If the flow value gets lower than ‘minimum cut-off’, the meter does not register any flow.
In the meter’s working range, from ‘minimum cut-off’ to ‘maximum cut-off’, there is a linear connection
between the quantity of water, which has passed through the meter and the measured water flow.
According to metrological and technical requirements/OIML R49, the upper flow limit (Q
4
/Max flow) is the
highest flow at which the flow meter may operate for short periods, without exceeding maximum
permissible error. The meter has no functional limitations during the period, when the meter operates
above this limit.
Please note, however, that high flow velocities > Q
4
(Max flow) involve the risk of cavitation, especially at
low static pressures below 0.03 MPa (0.3 bar).