KROHNE MFC 400 Profibus - Manual (Page 29)

COMMISSIONING / OPERATION
4
29
MFC 400
www.krohne.com 06/2013 - 4002835301 - AD MFC 400 PROFIBUS R01 en
Status = good (Non Cascade)
Status = Limits
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.
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
1 0 0 0 0 0 = ok
1 0 0 0 0 1 = update event
1 0 0 0 1 0 = active advisory alarm
1 0 0 0 1 1 = active critcal alarm
1 0 0 1 0 0 = unacknowledged update event
1 0 0 1 0 1 = unacknowledged advisory alarm
1 0 0 1 1 0 = unacknowledged critical alarm
1 0 1 0 0 0 = initiate fail safe
1 0 1 0 0 1 = maintenance required
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 = ok
0 1 = low limited
1 0 = high limited
1 1 = constant
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.