Weidmüller u-OS Data Hub

The Weidmüller connector enables bidirectional data exchange between your LogicCloud runtime and the Weidmüller u-OS Data Hub. You can publish PLC variables to the hub (provider) and subscribe to hub variables (consumer).

Prerequisites

Before creating a Weidmüller connection, you need:

1. A Weidmüller u-OS device with the Data Hub enabled
2. OAuth2 client credentials configured in the u-OS Control Center (Identity & access → Clients)
3. The exact client name as shown in Control Center

Client Name Must Match Exactly

The Client Name you enter in LogicCloud must match exactly what is configured in the u-OS Control Center. If it doesn’t match, connection requests will fail silently with no error message.

Silent Failures

The Weidmüller connector communicates with the u-OS Data Hub via NATS messaging. Due to how NATS addressing works, incorrect credentials or provider IDs cause silent timeouts — no error message is returned. If your connection appears stuck or variables aren’t updating:

1. Verify Client Name matches exactly (case-sensitive) what’s in u-OS Control Center
2. Verify Provider ID follows the naming rules (lowercase, starts with letter, no special characters)
3. Check edge device logs for registration or authentication errors

These are the most common causes of “nothing happens” scenarios.

Create a Weidmüller Connection

1. In your project, navigate to the Runtimes section
2. Select your runtime and expand Connections
3. Click Add connection and select Weidmüller
4. Fill in the connection details:

Field	Description
Name	A descriptive name for the connection
Client ID	The OAuth2 client ID from u-OS Control Center
Client Name	The exact client name from u-OS Control Center
Client Secret	The OAuth2 client secret
Token URL	The OAuth2 token endpoint (usually auto-detected)

5. Click Save to create the connection

Add a Provider (Publish to Hub)

Providers publish PLC runtime variables to the u-OS Data Hub, making them available to other systems.

1. Right-click the connection and select Add Provider
2. Configure the provider:

Field	Description
Name	A descriptive name for the provider
Provider ID	The hub provider identifier (lowercase letters, digits, underscores only)
Folder	Optional prefix for variable addresses (dot-separated)

3. Click Save

Provider ID Rules

The Provider ID must follow the u-OS naming grammar:

• Lowercase letters (a-z), digits (0-9), and underscores (_) only
• Must start with a letter
• Maximum 63 characters
• No dots, dashes, spaces, or uppercase letters

Valid: plc, weather_station, line1_sensors Invalid: PLC, plc-1, plc.line1, 1plc

Add a Consumer (Subscribe from Hub)

Consumers subscribe to u-OS Data Hub variables and write them to PLC runtime variables.

1. Right-click the connection and select Add Consumer
2. Configure the consumer (same fields as provider)
3. Click Save

Add Mappings

Mappings connect PLC variables to u-OS Data Hub variables.

1. Select the provider or consumer
2. Click Add Mapping
3. Configure each mapping:

Field	Description
Variable Name	The PLC runtime variable
Address	The hub variable address (dot-separated path)
Type	Data type: Bool, Int, Float64, String, etc.
Provider	Optional: override the endpoint’s provider ID for this mapping
Quality Variable	Optional: PLC variable for quality metadata
Timestamp Variable	Optional: PLC variable for timestamp metadata

Address Format

The hub variable address uses dot-separated segments:

Valid: temperature, line1.temp1, sensors.out.temp1 Invalid: 1temp, temp-1, temp/out

Folder Prefix

When you set a Folder on the provider/consumer, it is automatically prepended to each mapping’s address:

Folder	Mapping Address	Effective Address
sensors.out	temp1	sensors.out.temp1
plc.values	temperature	plc.values.temperature
(empty)	line1.sp1	line1.sp1

This allows organizing variables hierarchically without repeating the prefix in every mapping.

Data Types

Type	Description
Bool	Boolean (true/false)
Int	32-bit signed integer
Int64	64-bit signed integer
Float32	Single-precision floating point
Float64	Double-precision floating point
String	UTF-8 text
Duration	Time duration value
Timestamp	Date/time timestamp

Per-Mapping Provider Override

By default, all mappings in a provider/consumer use the endpoint’s Provider ID. You can override this per-mapping to publish/subscribe to a different hub provider:

1. In the mapping row, set the Provider field to a different provider ID
2. Leave it empty to inherit from the endpoint

This allows a single consumer to subscribe to variables from multiple hub providers.

Quality and Timestamp Metadata

Each mapping can optionally capture metadata reported by the u-OS Data Hub:

Field	Description
Quality Variable	A PLC variable that receives the hub-reported signal quality indicator. Useful for detecting stale or invalid data.
Timestamp Variable	A PLC variable that receives the hub-reported timestamp of the last value update. Useful for diagnostics and data synchronization.

These fields are optional. When configured, the edge runtime automatically populates them with metadata from the hub alongside the actual variable value.

Troubleshooting

Connection times out silently

Cause: The Client Name doesn’t match exactly what’s in u-OS Control Center.

Solution:

1. Open u-OS Control Center → Identity & access → Clients
2. Copy the exact client name (case-sensitive)
3. Update the connection in LogicCloud

”providerId is not a valid hub provider name”

Cause: The Provider ID contains invalid characters.

Solution: Use only lowercase letters, digits, and underscores. Must start with a letter.

Variables not appearing in the hub

Possible causes:

• Provider not registered (check edge device logs)
• Address doesn’t match the VariableName grammar
• OAuth2 token expired or invalid

Solution:

1. Check the edge device logs for registration errors
2. Verify the address uses only valid characters (letters, digits, underscores, dots)
3. Verify OAuth2 credentials are correct

Mappings are empty after deployment

Cause: Mappings weren’t saved correctly.

Solution: Re-open the provider/consumer, verify mappings are listed, and save again.