Endress+Hauser Proline Promag 300, Описание параметров устройства

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Description of device parameters Proline Promag 300 Modbus RS485
108 Hauser
0/4 mA value 
Navigation  Expert → Output → Curr.output 1 to n → 0/4 mA value (0367–1 to n)
Prerequisite One of the following options is selected in the Current span parameter (→  106):
• 4...20 mA NAMUR
• 4...20 mA US
• 4...20 mA
• 0...20 mA
Description Use this function to enter a value for the 0/4 mA current.
User entry Signed floating-point number
Factory setting Country-specific:
• 0 l/h
• 0 gal/min (us)
Additional information Description
Positive and negative values are permitted depending on the process variable assigned in
the Assign curr. parameter (→  106). In addition, the value can be greater than or
smaller than the value assigned for the 20 mA current in the 20 mA value parameter
(→  109).
Dependency
The unit depends on the process variable selected in the Assign curr. parameter
(→  106).
Current output behavior
The current output behaves differently depending on the settings configured in the
following parameters:
• Current span (→  106)
• Failure mode (→  116)
Configuration examples
Some examples of parameter settings and their effect on the current output are given in
the following section.
Configuration example A
Measuring mode with Forward flow option
• 0/4 mA value parameter (→  108) = not equal to zero flow (e.g. –250 m 3 /h)
• 20 mA value parameter (→  109) = not equal to zero flow (e.g. +750 m 3 /h)
• Calculated current value = 8 mA at zero flow
-250
20
+750
I [mA]
Q
1 1
4
0
8
A0013757
Q Flow
I Current
1 Measuring range is exceeded or undershot