KROHNE H250 M40 PROFIBUS PA - Manual (Page 20)

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COMMISSIONING / OPERATION
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H250 M40 ESK4
www.krohne.com 03/2014 - 4002251801 - AD H250/M40 PROFIBUS R01 en
Check the first two quality bits in order to get the quality information of the measurement value:
• Good (Non Cascade): Good (Non Cascade): Good (Non Cascade): Good (Non Cascade): function block output value is ok and can be used without restrictions
• Good (Cascade): Good (Cascade): Good (Cascade): Good (Cascade): will not be supported, because it is not applicable for the device
• Uncertain: Uncertain: Uncertain: Uncertain: function block output value can be used but the accuracy can not be guaranteed
(e.g. function block outputs value has been frozen or A/D converter is saturated or out of
range)
• Bad: Bad: Bad: Bad: function block output value is bad - don’t use it for process control!
The "Quality-Substatus" and "Limit" bits will be used for further diagnostics or limit checking.
Classic Status Classic Status Classic Status Classic Status
The Classic Status is implemented to provide compatibility to systems which are not configured
for Condensed Status. The coding is shown in the following table:
Status = bad
INFORMATION!
The status should be monitored because a number will be transmitted even if the status of the
measurement value is bad or uncertain. This is the only way to check the quality of the
transmitted measurement values.
Quality Quality substatus Limits
Gr Gr QS QS QS QS Qu Qu
2 7 2 6 2 5 2 4 2 3 2 2 2 1 2 0
0 0 = bad
0 1 = uncertain
1 0 = good (Non Cascade)
1 1 = good (Cascade) - not supported
Quality Quality substatus Limits
Gr Gr QS QS QS QS Qu Qu
2 7 2 6 2 5 2 4 2 3 2 2 2 1 2 0
0 0 0 0 0 0 = non-specific
0 0 0 0 0 1 = configuration error
0 0 0 0 1 0 = not connected
0 0 0 0 1 1 = device failure
0 0 0 1 0 0 = sensor failure
0 0 0 1 0 1 = no communication (last usable value)
0 0 0 1 1 0 = no communication (no usable value)
0 0 0 1 1 1 = out of service
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