Site Agents
Site agents are on-premises edge gateways that connect to PLCs, SCADA systems, and IoT devices on the shopfloor. They relay real-time tag readings to the ProBeya cloud platform, enabling live KPI dashboards and Andon displays powered by actual equipment data.
Overview
Each site agent is a lightweight software process running on an industrial PC or gateway device at your manufacturing site. It communicates with equipment using standard industrial protocols and streams data points to ProBeya over a secure connection.
Supported Protocols
| Protocol | Use Case |
|---|---|
| OPC-UA | Modern industrial automation standard (Siemens, Beckhoff, Rockwell) |
| MQTT | Lightweight pub/sub messaging for IoT sensors |
| S7comm | Native Siemens S7 PLC communication |
| Modbus | Legacy protocol for meters, drives, and sensors |
| REST | HTTP-based data collection from web-enabled devices |
Getting Started
- Navigate to Settings > Site Agents.
- Click Create Agent.
- Enter the agent name and optional site ID for grouping (e.g., "SITE-BRU-01").
- Select the protocol used to communicate with the equipment.
- Provide the connection configuration (host, port, credentials, etc.).
- Define the data point tags -- each tag maps to a specific equipment address.
- Save the agent. It starts in offline status until it sends its first heartbeat.
How It Works
Agent Lifecycle
| Status | Meaning |
|---|---|
| Offline | Agent is registered but has not sent a heartbeat |
| Online | Agent is actively sending heartbeats and data |
| Error | Agent reported an error (e.g., PLC communication failure) |
| Maintenance | Agent is intentionally taken offline for maintenance |
The agent sends periodic heartbeat messages. Each heartbeat updates the status to online and records the timestamp. If heartbeats stop arriving, monitoring processes can flag the agent.
Data Points
Each data point represents a single tag reading from an equipment address:
| Field | Description |
|---|---|
| Tag Name | Logical identifier (e.g., "Temperature_Reactor_1") |
| Address | Equipment-specific address (e.g., OPC-UA node ID, Modbus register) |
| Data Type | Value type (float, int, bool, string) |
| Scan Interval | Polling frequency in milliseconds |
| Value | The numeric or string reading |
| Quality | Signal quality indicator (good, bad, uncertain) |
| Timestamp | When the reading was taken on the equipment |
Latest Values
The Get Latest Values endpoint returns the most recent reading for each configured tag on an agent. This powers real-time dashboards and Andon displays with a single API call.
Configuration
| Setting | Description |
|---|---|
| Name | Human-readable agent name |
| Site ID | Physical site grouping identifier |
| Protocol | opcua, mqtt, s7comm, modbus, or rest |
| Connection Config | Protocol-specific JSONB (host, port, auth, TLS settings) |
| Data Points | Array of tag definitions (tagName, address, dataType, scanIntervalMs) |
Permissions
- Organization Admins and Owners can create, update, and delete site agents.
- All agent data is scoped to the current organization for multi-tenant isolation.
- Deleting an agent permanently removes all its historical data point readings.
Tips & Best Practices
Use meaningful tag names that follow a naming convention (e.g., Area_Equipment_Measurement). This makes it easier to map tags to KPI definitions later.
Deleting a site agent is a destructive operation -- all historical data points from that agent are permanently removed. Consider setting the status to maintenance instead if you plan to reconnect later.
- Group agents by Site ID to filter and manage agents across multiple manufacturing locations.
- Start with a small set of critical tags and expand once connectivity is proven.
- Monitor heartbeat timestamps to detect agents that have gone silent.
- Use OPC-UA where available -- it provides the richest metadata and security model.
- Keep scan intervals reasonable (1-10 seconds for process data, 60+ seconds for environmental sensors).
Related Features
- Andon Configuration -- Display live agent data on shopfloor screens.
- Connectors -- ERP/MES connectors for enterprise system integration.
- Integrations -- Push data events to external systems via webhooks.