I haven't worked with this particular equipment, but it shouldn't be too hard. I was able to find an online manual for working with their ph meters and the command structure is very simplistic since it was apparently designed to be used with nothing more than a dumb terminal. If you are missing the manual for your meter check:
http://www.thermo.com/eThermo/CDA/BU_Home/BU_Homepage/0,1285,161,00.html
If that link doesn't work got to www.thermo.com and click on "Visit Thermo's Business Units" and select Thermo Orion under the "Environmental Instruments Division".
Hope this helps...
Mike...