à¤Ã×èͧÇÑ´¤èÒ pH + ORP WQ500 Extech Benchtop Water Quality Meter/Stirrer Magnetic stirrer with pH, mV, and Temperature measurements Features : Built-in stirrer with 30, 60, and 120 minute timer or continuous operation Large backlit dual LCD simultaneously displays measurement and temperature 2 or 3 point pH calibration for better accuracy (4, 7, and 10pH) Automatic Temperature Compensation Memory stores up to 150 readings Readings can be captured directly to a PC via the buili-in USB interface Splash-proof keyboard Complete with pH glass electrode & pH calibration solutions (4 and 7 ph), temperature probe, electrode clamp and rod, software and USB cable and AC adapter and Stirrer Specifications : pH -2.00 to 16.00pH ORP -1999 to +1999mV Temperature 32 to 212ºF (0 to 100ºC),pH Conductivity - TDS - Salinity - Dissolved Oxygen - Resolution 0.01 pH, 0.1mV, 0.1μS, 0.1 mS, 0.1º, 0.1ppm, 0.1ppt, 0.1mg/L, 0.1% Accuracy ±0.01pH; ±2mV; ±0.2ºF/ºC; ±2%FS for other parameters Power 100 to 240V AC adapter with US, EU, UK, and AU plugs Dimensions/Weight (Meter) : 4×5.7×1.3" (103×145×32mm) / 1.5lbs (700g)