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Proline Promag 51
Commissioning
Hauser
55
6.1.4
Special features of operation subject to metrological control/
custody transfer measurement
Measuring devices subject to legal metrological control differ from standard devices as follows:
• Once the device has been placed on the market/put into operation or lead-sealed, it can no longer
be operated using the local display.
• Flowmeters for legal metrological control totalize bidirectional flow, i.e. all outputs consider flow
shares in positive (forward) and negative (backward) flow direction.
6.1.5
Definitions
Cold water
Fluid temperature b0.1 °C and +30 °C
Flow ranges
Overload flowrate Q
:
Highest flowrate at which a water is required to operate, for a short period of time, within its
maximum permissible error, without deteriorating.
Permanent flowrate Q
3
:
Highest flowrate within the rated operating conditions, at which the water meter is required to
operate in satisfactory manner within the maximum permissible error.
Transitional flowrate Q
2
:
Flowrate which occurs between the permanent flowrate Q
3
, and the minimum flowrate Q1, that
divides the flowrate range into two zones, the upper flowrate zone and lower flowrate zone, each
characterized by its own maximum permissible error (
42).
A0011455
Fig. 42:
Flow ranges and error limits for cold water
1 = Lower range (error limit: ±5%)
2 = Upper range (error limit: ±2%)
Minimum flowrate Q
1
:
Lowest flowrate at which the water meter is required to operate within the maximum permissible
error.
Q1
Q3
Q2
±5
%
Q [m /h]
3
±2
0
1
2
Q4
Содержание HART Proline Promag 51
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