Endress+Hauser promag 31, Operating Manual

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Operation
Inside the housing of the transmitter there are miniature switches with which
altogether six operating parameters can be set (see Chapter 4):
•
Current range 0/4...20 mA
•
Full-scale value scaling (volume/time), 8 steps
•
Pulse weighting in decadic steps (volume), 8 steps
•
Engineering units
•
Function of the status output
Output of system/process errors
Flow direction recognition
•
Creep suppression (on/off)
Local display
Using the Promag 31 local display, important parameters can be read off and control-
led at the measuring point directly:
•
Flow rate and/or totaliser value
•
Technical units (SI/US units)
(US-conformity with fiscal measuring systems is not available)
•
Process variables (e.g. creep rate, partial pipe filling)
•
Error messages
Using the three operating keys, it is also possible to select and activate various
functions. A small pin is used to press the keys down (keep pressed for
approx. 0.5...0.8 s).
•
After the unit has been certified for fiscal metering, it is sealed and it is not possible
to self programe the unit.
Dynamic response
The Promag 31 measuring amplifier has a very high dynamic response of over
1000:1. It measures at medium velocities from less than 10 mm/s to over 10 m/s with
the specified accuracy. When the flow is pulsating, the amplifier is not over-driven
even above the end value setting at maximum speeds up to 12.5 m/s. There is then
no falsification of the measured value, provided the outputs are not over-driven.
Fiscal acceptance
Note!
Fiscal, magnetic-inductive flow meters may (in contrast to mechanical meters) be
operated with Q
100
= Q
max
.
Warning!
Only a custody transfer certified flowmeter can be used for cold water fiscal metering.
Fiscal-capability
Note!
Fiscal-capable flowmeters for custody transfers are not approved of by the standards
authority. These meters are however technically identical to fiscal flowmeters.
These meters may not be used in fiscal-bound custody transfers.
The fiscale-capable flowmeter can however can be examined and approved of by an
official standards authority through discussion at a later point in time.
Mass-measuring systems with a maximum flow of >2000 m
3
/h are exempted from
fiscal-standards. These measuring systems will not be fiscal, but they could be
fiscal-capable.
Promag 31 1. System Description
Hauser 9