W-Modbus: Pairing a Field Device with a Gateway

In this video setup guide, we'll show you how to connect a gateway to a field device via W-Modbus. Pairing the gateway involves three simple steps:

  1. Enable pairing (open connections)
  2. Pair devices (establish connection)
  3. Disable pairing (secure connections)
Back to blog

Instructional Video

W-Modbus Pairing

To pair a wireless device with a gateway, both devices must be set to pairing mode (learning mode). This also applies if the device is to be integrated into an existing network. During this process, devices that are already paired are automatically switched to pairing mode and re-paired. Within the immediate vicinity (radio range), only a single master gateway (RS485 bus) may be in pairing mode at any given time!

Excerpt from the User Manual

1. Enable pairing (open connections) Activation on the master gateway is performed using DIP switch [W]: DIP 1 → ON (pairing active – open connection – status LED L1 flashes orange); DIP 2 must be set to ON. Please refer to the device-specific user manual for instructions on how to enable or disable pairing mode on the W-Modbus device.
2. Pairing Devices (Establishing a Connection) All wireless devices in active pairing mode automatically search for a master gateway that is also in pairing mode. This initial connection takes about 1–2 minutes. A temporary connection is now established, which can be secured as described in Step 3. After about 2–3 minutes, bus communication can already be tested and data exchanged during this phase.
3. Disable pairing (secure connections) Once all devices have been successfully paired, the user must manually complete the pairing process on the master gateway: DIP 1 → OFF (pairing deactivated – secure connection – status LED L1 lights up orange). This automatically deactivates pairing on the paired devices. The wireless devices then perform an automatic restart and establish a secure connection. Modbus communication is restored within 2–3 minutes. A permanent connection is thus established and remains active even after a power cycle. Data exchange during normal operation can now begin.

Click here for the complete user manual