541. IntroductionThank you for selecting an OAKTON meter. This OAKTON portable meteris a microprocessor-based instrument that measures pH, conductivity, TDS andtemperature! Your meter has many user-friendly features, all of which are accessiblethrough the membrane keypad.Your meter includes a single-junction pH electrode, a combination conductivity/temperature probe, and batteries. Please read this manual thoroughly beforeoperating your meter.2. Display and Keypad FunctionsDisplayThe LCD has a primary and secondary display.• The primary display shows the measured pH or conductivity reading.• The secondary display shows the temperature of the reading.The display also shows error messages, keypad functions and program functions.mSATCREADYMEAS CALHOLDERR FSETUPONOFF CμSK=pH%mVpHpptppm2.1Primary displaySecondary display3.2.2120.14.17.16. 15.13.1.19.18.4.6.5.11.12.7.8.pH/Conductivity/°C/°F MeterpH/CON 300 SeriesWATERPROOFMODEHOLDENTERRANGEONOFFCALMEASstSETUPATCREADYMEASCμS1. SETup mode indicator2. MEASurement modeindicator3. CALibration indicator4. mV indicator5. % indicator6. pH measurementindicator7. Millisiemens indicator8. Microsiemens indicator9. Parts per thousandindicator10. Parts per millionindicator11. Temperatureindicators12. pH setup indicator13. AutomaticTemperatureCompensationindicator14. ERRor indicator15. Low battery indicator16. Probe indicator17. Calibration indicator18. Cell constant indicator19. ON/OFF indicator20. HOLD indicator21. READY indicator9.10.