# S3 node version

S3 is a version of S2 node that which is used to connect the sensor directly to a PC over the RS232 port.

It is a single node with a sensor that is connected to the PC serial port. From the monitoring system point of view it behaves as an S2 PC node communicating with a single S2 measuring node which have a sensor or sensors connected to it. It is possible to connect only one S3 node to a single serial port.

There are S3 versions of many node types listed in [s2-node-types](https://help.boomerang3.com/s2-radio-system-manual/s2-system-description/s2-node/s2-node-types "mention").