Sample System Requirement and Solution
This example includes a sample system requirement, and the resulting ClearSCADA configuration required to fulfill such a requirement.
The example builds on the concepts that are detailed in the previous Configuration Examples in this section.
Example:
Requirement:
The Simple Modbus driver on a ClearSCADA system is required to scan the following points on a Modbus PLC:
Four analog points, comprising one at each of these locations:
- 3:00005 (INT)
- 3:00010 (DINT)
- 3:00100(REAL)
- 4:00011 (UINT).
Five digital points, comprising one at each of these locations:
- 3:00012 bit offset 5
- 1:00005
- 0:00006
- 1:00009
- 1:00025.
Solution:
To fulfill the above requirement, five Modbus Scanners are needed to scan these data ranges:
- 0:00006
- 1:00005 to 1:00025
- 3:00005 to 3:00012
- 3:00100 to 3:00101
- 4:00011
(The two ranges within the 3: range are scanned separately to avoid needlessly scanning 88 unused registers in between the required ranges.)
These Modbus Scanners are configured within ClearSCADA:
Configuration Field on Modbus Scanner Form | Required Scanner Range | ||||
---|---|---|---|---|---|
0:00006 | 1:00005 to 1:00025 | 3:00005 to 3:00012 | 3:00100 to 3:00101 | 4:00011 | |
(Scanner) Name |
Output Coils |
Input Discretes |
Input Registers Low |
Input Registers High |
Holding Registers |
Data Address |
5 |
4 |
4 |
99 |
10 |
Data Length |
1 |
21 |
8 |
2 |
1 |
Location |
Output Coils |
Input Discretes |
Input Registers |
Input Registers |
Holding Registers |
Address Base |
1 |
1 |
1 |
1 |
1 |
These Modbus Analog Points are configured within ClearSCADA:
Configuration Field on Modbus Analog Point Form | Required Analog Point Data | |||
---|---|---|---|---|
3:00005 (UINT) | 3:00010 (DINT) | 3:00100 (REAL) | 4:00011 (UINT) | |
Scanner (with which the point is associated) |
Input Registers Low |
Input Registers Low |
Input Registers High |
Holding Registers |
Word Offset |
0 |
5 |
0 |
0 |
Data Type |
UINT |
DINT |
REAL |
UINT |
These Modbus Digital Points are configured within ClearSCADA:
Configuration Field on Modbus Digital Point Form | Required Digital Point Data | ||||
---|---|---|---|---|---|
0:00006 | 1:00005 | 1:00009 | 1:00025 | 3:00012 Bit Offset 5 | |
Number of Bits |
1 |
1 |
1 |
1 |
1 |
Scanner (with which the point is associated) |
Output Coils |
Input Discretes |
Input Discretes |
Input Discretes |
Input Registers Low |
Word Offset |
0 |
0 |
0 |
1 |
7 |
Bit Offset |
0 |
0 |
4 |
4 |
5 |