4
D0 indicates that the channel outputs digital when the analogue input is A0 and D1 indicates that the channel outputs digital when
the analogue input is A1
Channel
D
Digital Output
A
Analog Input
Channel model
D1
A (0.1
℃
)
Channel Characteristics
D0
A0
A1
P1
P0
D(0.1
℃
)
Figure 3-1 Schematic diagram of VC-4PT channel characteristics
(2) The measurement error is caused by the impedance of the connection cable, which can be eliminated by setting the channel
characteristics.
(3) Considering the user's ease of use and without affecting the function, in the current mode, A0 and A1 are corresponding
to [Actual Value 1] and [Actual Value 2] respectively, and D0 and D1 are corresponding to [Standard Value 1] and [Standard
Value 2] respectively, as shown in Figure 3-1, the user can change the channel characteristics by adjusting (A0,D0) and (A1,D1),
the factory default (A0,D0) As shown in Figure 3-2, A0 is 0, A1 is 6000 (unit is 0.1
℃
)
Figure 3-2 Channel characteristics for each mode without changing the D0 and D1 values of each channel
(4) If the VC-4PT measurement value is 5°C (41°F) higher in actual use, the error can be eliminated by setting the two points
P0 (0, -50) and P1 (6000, 5950) of the characteristic adjustment, see Figure 3-3 for an example.
Figure 3-3 Example of characteristic change
4 Programming example
4.1 Programming example for VC VC-4PT module
As shown in the example below, the VC-4PT is connected to position 1 of the expansion module and uses channel 1 to connect to
a Pt100 RTD to output Celsius temperature, channel 2 to connect to a Cu100 RTD to output Celsius temperature and channel 3 to
connect to a Cu50 RTD to output Fahrenheit temperature, with channel 4 switched off and the number of average points set to 8
and the data registers D0, D1 and D2 to receive the The average value conversion result. The settings are shown in Figure 4-1 to
Figure 4-3. See the VC Series Programmable Controllers Programming Reference Manual for further details.
1)
Create a new project and configure the hardware for the project as shown in the figure below.
6 0 0 0
- 1 0 0 0
0
- 9 5 0
A ( 0 .1
℃
)
D ( 0 .1
℃
)
P 0
P 1
- 5 0
5 9 5 0
D 0 = - 5 0 ; D 1 = 5 9 5 0
6000
6000
－
1000
0
Factory setting (no adjustment)
－
1000
A
（
0.1
℃）
D
（
0.1
℃）
