Siemens SITRANS FEC920, Руководство пользователя

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FEC920: USER GUIDE
Page 88 September 18
6.5.4 Counter configuration
This allows the user to set up a counter to count trigger inputs (or it may be incremented from the Configuration
page. The Rollover Value of the counter is configurable (default 1,000,000). Counters can be cascaded by wir-
ing from ‘Rollover’ of one counter to ‘trigger’ of the next. Wiring is carried out from the operator interface (Section
10) or in iTools
( Section 9).
For ‘Trend’, ‘Alarm 1’ and ‘Alarm 2’ configurations please see the relevant parts of Section 6.4.
Figure 79 Typical Counter configuration
Descriptor Allows the user to enter a descriptor (20 characters max.) for the counter.
Type Select: Math, Counter or Totalizer.
Operation Allows the user to enable (‘On’) or disable (‘Off’) the counter.
PV Read only. Shows the dynamic value of the counter.
Status Read only. Reflects the status of the input channel.
Resolution Allows the number of decimal places (up to six) to be defined for the channel.
Units Allows a units string of up to five characters to be entered for the counter value.
Low Cut Off Specifies a value below which the counter will not decrement.
High Cut Off Specifies a value above which the counter will not increment.
Input1 The amount by which the counter is incremented each time ‘Trigger’ goes high. The value
may be entered manually, or wired from another parameter. Negative values cause the
counter to decrement.
Preset Setting this to ‘Yes’ causes the counter to adopt its Preset Value. The field returns
immediately to ‘No’. The counter can also be preset by wiring from another parameter.
Preset Val Allows the entry of a value, from which the counter is to start incrementing or
decrementing.
Trigger Setting this to 1, causes the current value of the input source to be added to the Counter
value. This function can be carried out manually, or the input can be wired from another
parameter (Section 10.2).
VirtualChan1
Counter
On
123436 units
Good
0
units
Descriptor
Type
Operation
PV
Status
Resolution
Units
Virtual Channel.1.Main
Low Cut Off
High Cut Off
Input1
Preset
Preset Value
Trigger
Rollover
Rollover Value
Disable
0
999999
015.3241
0
0
No
No
1000000
Figure 78 Cascading counters
etc.
Counter 1
Counter 2
Counter 3
Input 1
Input 1
Input 1
Rollover
Rollover
Rollover
1 to 10
6
10
6
to 10
12
10
12
to 10
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