Overview
This section provides detailed technical specifications for integrating and configuring the Dilution Control System. Use this reference for advanced configuration, PLC programming, and system integration.
Modbus Registers
Complete register map for Modbus TCP/RTU communication
Status Codes
Zone and actuator status bit definitions
System Specifications
Capacity
| Parameter | Specification |
|---|---|
| Maximum Zones | 256 |
| Maximum Scanner Databoxes | 500 |
| Profile Update Rate | 100ms - 5000ms (configurable) |
| Control Interval | 30s - 300s (configurable) |
| Saved Grades | Unlimited |
| Alarm History | 100,000 records |
Performance
| Parameter | Specification |
|---|---|
| Modbus Response Time | < 50ms typical |
| Profile Processing Time | < 20ms (200 databoxes) |
| Display Update Rate | 100ms |
| Data Logging Rate | 1 second minimum |
Communication Protocols
Supported Protocols
| Protocol | Purpose | Port |
|---|---|---|
| Modbus TCP | Primary PLC communication | 502 (default) |
| Modbus RTU | Serial PLC communication | COM port |
| S7-TCP (SNAP7) | Siemens PLC communication | 102 |
| Beckhoff ADS | TwinCAT communication | 48898 |
| OPC DA | QCS integration | N/A |
Modbus Function Codes
| Code | Function | Usage |
|---|---|---|
0x03 |
Read Holding Registers | Read feedbacks, status |
0x04 |
Read Input Registers | Read scanner data |
0x06 |
Write Single Register | Individual zone control |
0x10 |
Write Multiple Registers | Batch setpoint writes |
Data Types
Register Data Types
| Type | Size | Range | Usage |
|---|---|---|---|
INT16 |
1 register | -32768 to 32767 | Status, scaled values |
UINT16 |
1 register | 0 to 65535 | Unsigned integers, positions |
INT32 |
2 registers | -2.1B to 2.1B | Counters, timestamps |
FLOAT32 |
2 registers | IEEE 754 single | Setpoints, feedbacks, profiles |
Byte Order
The system supports configurable byte order for multi-register values:
- Big Endian (AB CD): Most significant byte first
- Little Endian (CD AB): Least significant byte first
- Big Endian Byte Swap (BA DC): Word-swapped big endian
- Little Endian Byte Swap (DC BA): Word-swapped little endian
Byte Order Selection
Select byte order to match your PLC configuration. Most Siemens PLCs use Big Endian, while many other PLCs use Little Endian. Test with known values to verify.
Value Scaling
Position values are typically scaled as percentages (0-100%). When using integer registers:
Engineering Value = (Register Value × Scale) + Offset
Example (0-32767 to 0-100%):
Scale = 100 / 32767 = 0.003052
Position = Register × 0.003052