KROHNE VFC 200, Дополнительное руководство по инструкции

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COMMISSIONING / OPERATION
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VFC 200
www.krohne.com 06/2019 - 4005059401 - AD VFC200 PB-PA 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.
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
Table 3-10: Coding for "Status = good (Non Cascade)"
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
Table 3-11: Coding for "Status = Limits"
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.