TPU2000/2000R Modbus/Modbus Plus Automation Guide
79
Within following discussions of scaling parameters, it should be remembered that the bit scale shall be referred to
as the quantity “N” which is used extensively for the final scaled value calculation. N shall be a value of 16,12,8,4,
or 2, which corresponds to the Bit Scale type referred to in Table 5-10 above.
Unscaled
Value In The
DPU2000R
Scaled
Value Reported To
the Host Via Network
0
+ Full Scale
Table 2 Minimum Value
Table 2 Maximum Value
I
f
P
R
I
M
A
R
Y
V
A
L
U
E
I
S
N
E
G
A
T
I
V
E
‘
0
”
I
S
R
E
T
U
R
N
E
D
UNIPOLAR
SCALING
Unscaled
Value In The
DPU2000R
Scaled
Value Reported To
the Host Via Network
0
- Full Scale
Table 2 Minimum Value
Table 2 Maximum Value
I
F
P
R
I
M
A
R
Y
V
A
L
U
E
I
S
P
O
S
I
T
I
V
E
0
I
S
R
E
T
U
R
N
E
D
NEGATIVE
UNIPOLAR
SCALING
Unscaled
Value In The
DPU2000R
Scaled
Value ReportedTo the
Host Via Network
- Full Scale
0
+ Full Scale
Table 2 Minimum Value
0
BIPOLAR
SCALING
Unscaled
Value In The
DPU2000R
Scaled
Value ReportedTo the
Host Via Network
- Full Scale
0
+ Full Scale
Table 2 Minimum Value
Table 2 Maximum Value/2
OFFSET
BIPOLAR
SCALING
Table 2 Maximum Value Table 2 Maximum Value
Figure 5-29. Relationship Between Scaled and Unscaled Formats for Offset Bipolar, Bipolar,
Unipolar, and Negative Unipolar Scaling Selection in the TPU2000 and 2000R
If one were to mathematically compute the minimum and maximum values as described above in Table 5-10 and
relate the values to the unscaled full scale + and full scale – values, the following equations would result from the
analysis.
Data Type Definitions Value Ranges
EQUATION 1:
Offset Bipolar (0 to +2
N
-1) where 0 = -FS, 2
N-1
-1 = 0 and 2
N
-1 = +FS
EQUATION 2:
Bipolar (-2
N-1
to + 2
N-1
-1) where -2
N-1
= -FS, 0 = 0 and 2
N-1
-1 = +FS
To Next Page
Loading...
Need help?
General
