Siemens FEC920 User Manual page 92

Flow energy calculator
Hide thumbs Also See for FEC920:
Table of Contents

Advertisement

Figure 76 shows a typical totalizer configuration page.
Virtual Channel.1.Main
Resolution
Units Scaler
Low Cut Off
High Cut Off
Preset Value
Rollover Value
Descriptor
Type
Operation
PV
Status
Resolution
Units
Units Scaler
Low Cut Off
High Cut Off
Page 84
Descriptor
VirtualChan1
Type
Totaliser
Operation
On
PV
180.3625 units
Status
Good
4
Units
units
1
0
100000
Input1
327.1
Period
1 sec
Preset
No
0
Rollover
No
1000000
Disable
Figure 76 Typical totalizer configuration menu
Allows the user to enter a descriptor (20 characters max.) for the totalizer.
Select: Math, Counter or Totalizer.
Allows the user to enable ('On') or disable ('Off') the totalizer.
Read-only. This is the dynamic output value of the totalizer.
Read-only. Shows the status of the totalizer.
The Resolution parameter allows the number of decimal places (up to six) to be set for the
totalized value as displayed on the instrument panel. It does not affect the resolution of
the totalization process. Up to six decimal places may be set for the totalized value.
Allows a units string of up to five characters to be entered for the totalized value.
Allows a units scaler to be selected. Typically this will be used to scale between unit types
rather than to influence time period.
One example of this would be when an input is measured in Litres/Minute, and Period has
been set to 1Minute. If UnitsScaler is set to 1 then the total volume will be measured in
Litres. If the volume is required in Cubic Metres then conversion of the total will be needed.
There are 1000 Litres in a Cubic Metre so the UnitsScaler should be set to 1000. This
produces an additional division of 1000 and results in a total output in Cubic Metres.
Another example would be a requirement for the output in Gallons rather than litres, still
with an input being measured in Litres/Minute. There are 4.54609 litres in an imperial
gallon so the UnitsScaler would be set to 4.54609. (For a US Gallon the figure would be
3.78541.)
Used to restrict the input operating range of the totalizer. Minimum value = -100 000
Used to restrict the input operating range of the totalizer. Maximum value = 100 000
Low Cut Off and High Cut Off are particularly important as they directly affect the
totalization process. Together these two parameters define the range of valid inputs to the
totalization process. If Input1 value lies between them, then the input is considered valid
FEC920: USER GUIDE
Figure 75 Using cascaded counters to expand
A5E45696052A Rev-AA
Totalizer
Input 1
Rollover
6
1 to 10
Counter 1
Input 1
Rollover
6
12
10
to 10
Counter 2
Input 1
12
10
to 10
the totalization range.
Rollover
18
September 18

Advertisement

Table of Contents
loading

Table of Contents