The WEBRELAIS external relay module operates as a network device with a built-in web server. It can be controlled by HTTP, API calls, or automation systems, including from the Robin intercom device. 

The module supports protocols such as Modbus/TCP and XML. 

Up to 4 independent relays can be controlled. Each one is separately configurable to manage up to 4 different doors, gates, lights, or other devices. 

The WEBRELAIS supports PoE (Power over Ethernet) or can be powered via a 9-28Vdc power supply.

It can be controlled either via local network or over the internet, depending on the network configuration for your project. 

This kind of setup enables deployments to be more scalable in settings such as offices with multiple entrances, industrial sites, and residential complexes.