Can I use RS-485 transmission?

Yes. Instruments can be configured to transmit realtime data using full-duplex RS-485.  

Standard instruments need an appropriate external battery end-cap (either USB, RS-232, or RS-485) for the required external communication mode, selected at the time of purchase, as the wiring differs between the options.  Ruskin will then configure the instrument with the applicable streaming data serial option.  For RS-485 communication, you will also need an RS-485 converter at the receive end.