To connect several sensors to each port we have developed the Y-cable. It splits one physical port into two, and lets you thus connect to the same port e.g. a Rain Gauge and a Temperature/Humidity combi sensor.
Attention: you will still need to pay attention not to connect two sensors which use the same cabling to the different branches of a Y-cable! At the end the Y-cable still connects to ONE I/O port on the RTU, which offers three analog channels, one each on cabling 1, 2 and 3 respectively. Example: you connect a SEN-R combi sensor, which uses cabling 1 and 2 for temperature and humidity, to one connector of the Y-cable. Therefore to the other connector of the Y-cable you can only connect a sensor that is NOT using cabling 1 or 2, but only cabling 3, or has a pulse output (such as a rain gauge) or a digital status (such as a switch).