Endress+Hauser Proline Promag 55 PROFIBUS PA, Руководство по эксплуатации

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Commissioning Proline Promag 55 PROFIBUS PA
90 Hauser
Example of using the SETTOT_MODETOT_TOTAL module
If the SETTOT function is set to 1 (= reset the totalizer), the value for the aggregated total is reset
to 0.
If the aggregated total of the totalizer should constantly retain the value 0, the MODETOT function
must first be set to 3 (= totalizing is stopped) and then the SETTOT function must be set to 1 (=
reset the totalizer).
DISPLAY_VALUE module
Using the DISPLAY_VALUE module (slot 6), the PROFIBUS Master (Class 1) can transmit a cyclical
value to the measuring device, which can be used either as a display value for the onsite display or
as a density value for calculating mass flow. The assignment of the transmitted value to the device
function is done using the CONTROL_BLOCK (slot 7).
Option 1
→
Display value
If the value transmitted to the device is to be displayed on the onsite display, the output byte of the
CONTROL_BLOCK (slot 7) must be changed from 0 -> 61. The assignment of the display value to
the main, additional or info line can be configured using the onsite display itself or using an
operating program (e.g. FieldCare).
Output data
Option 2
→
Density value for calculation of mass flow
If the density value transmitted to the device is to be used for the continuous calculation of mass
flow, the output byte of the CONTROL_BLOCK (slot 7) must be changed from 0 -> 60.
Output data
Status
• General:
Implementation in accordance with PROFIBUS PA profile specifications, version 3.0.
• Behavior when status condition is GOOD:
If a density value with the status GOOD is transmitted, this value is converted into the current
system unit and processed in the measuring device.
• Behavior when status condition is BAD and UNCERTAIN:
If a density value with the status condition BAD or UNCERTAIN is transmitted to the device, a
density value of 0 is used to calculate mass flow. If a measured variable (e.g. mass flow), which
has been calculated using the density value, is transmitted cyclically to the PROFIBUS Master
using the AI module, then the status information of the quality byte is dependent on the fault
behavior configured in the FAILSAFE_TYPE function of the analog input function block.
Byte 1 Byte 2 Byte 3 Byte 4 Byte 5
Display value (IEEE 754 floating point number) Status
Byte 1 Byte 2 Byte 3 Byte 4 Byte 5
Display value (IEEE 754 floating point number) Status