Description/Composition
The DGP board (Data Gathering Panel) serves as the interface between house-level sensors/actuators and the Integra system, which runs on IntraE PCs located in the barns or on the central V20 computer.
Each DGP is powered by a 12V power supply, internally regulated to 5V. The board contains 8 channels, each of which can function as:
- Input (Analog or Digital):
Each input includes three terminals: Input, Common, and Shield — and is used to receive data from field sensors such as temperature probes, switches, or water pressure sensors. - Output (Digital Relays):
Each full DGP has 9 output relays. The first eight relays receive on/off signals from the DGP’s processor and are used to control higher-current 24V relays located in the Relay Control Unit (RCU) or Motor Control Unit (MCU).
These relays feature:- One input terminal
- Both normally open (NO) and normally closed (NC) contact terminals
The ninth relay functions as a watchdog, dropping out when communication with the PC is lost or power is interrupted, triggering backup mode in the house.
Illustration only, the actual boards might show variations.
Counters
The counter function is one of the most critical features of DGP boards. It allows the system to track pulse-generating events such as egg counting, water usage, and scale dumps. Counter inputs are provided via dedicated daughter boards mounted on the main DGP board.
There are four types of counter daughter boards, each offering different functionalities:
1. Counter Only Board (Model CNT/0)
- Basic board with no outputs or communication channels.
- Used strictly for pulse-counting devices.
- Ideal for large-scale systems where many counters are needed without added complexity.
2. Counter/Analog Output Board (Model CNT/A#)
- Includes counter inputs and 2, 4, or 8 analog outputs on the right side.
- Analog outputs (0–10 VDC) are used to control variable-speed fans or motors.
- Combines pulse input and output control in one module.
3. Counter/RS232 Board (Model CNT/RS232)
- Combines 8 counters with an RS232 communication port.
- RS232 is used for integrating digital scales or ASCII terminals.
- Useful for weight tracking systems or smart monitoring devices.
4. Counter/Relay Output Board
- Provides 8 counters and 8 additional relays (output).
- No watchdog protection, so its use is limited and not recommended for critical control.
- Rarely used in modern installations.
Communications
Communication between the central PC and DGP boards begins with a serial RS232 port, typically COM1 or COM2.
Since RS232 supports only one device over a short distance (~50 feet), an intermediary device is required to extend communication and support multiple endpoints.
Spider Hub Interface (RS422)
The RS232 port on the PC connects to the RS232 input module on the Spider Hub. A surge protector is recommended between the PC and Spider Hub to prevent damage from surges. The Spider Hub translates RS232 into RS422.
The Spider Hub uses RS422 output modules to distribute communication to the DGP boards. Each output module on a Spider Hub supports communication up to 16 DGPs and a distance of up to 4000 feet.
Splitter boards (Optical fiber)
When fiber optic communication is used instead of RS422, the architecture changes slightly to include splitter boards at the house level:
As before, the PC communicates via RS232, which is converted by the Spider Hub. Instead of RS422 modules, fiber output modules are installed on the Spider Hub.
Each fiber module sends and receives light signals over fiber optic cables, which. The fiber optic cable connects to a Splitter Board in each house. This Splitter Board is a compact version of the Spider Hub with
- One fiber receive channel
- Two RS422 output channels (to communicate with local DGPs)
- Power for the splitter is supplied from a terminal strip inside the DGP cabinet.
The Splitter Board converts fiber signals back to RS422, which is then routed to the local DGP boards using standard RS422 wiring.
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