SL7000 User Guide
Drawing No: SIG-1135-01-17
Page 15 of 30
Change Note: CN0054
10.5
Input Scaling:
This is only active for the process inputs (Current, Voltage and Counter input) and enables the inputs to be scaled
in engineering units. The units can be entered as a string and will appear on printouts etc, this option only appears
if the Icon box is set to ‘None’. The Icon box enables an appropriate icon to be displayed on the LCD display, If
selected other than ‘None’ this is also used for the ‘units’ field on graphs etc.
How to enter your scaling.
Use to following equation to calculate the Engineering High and Low values to enter into the issue screen.
Where:
A = Electrical high.
B = Electrical low.
C = Input engineering range low.
D = Input engineering range high.
E = Electrical span.
(calculated)
F = Input engineering range span.
(calculated)
G = Gain.
(calculated)
Z = Range High.
X = Range Low.
If A = Z and B = X then Engineering Low = C and Engineering High = D. These values can be entered directly into
the issue screen.
If A not equal Z and B not equal X then use the following equations.
E = A – B
F = D – C
G = F / E
Engineering High = (( Z – B ) * G ) + C
Engineering Low = (( X – B ) * G ) + C
Input Range
Range Low
(X)
Range High
(Z)
4 to 20mA
4
20
±100mV
0
100
0 to 1V
0
1
0 to 10V
0
10
Counter
0
65535
Z
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B
X
C
D
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