The HI9813-5 portable meter features a large LCD which displays either pH, EC, TDS or temperature readings along with tutorial instructions.. The pH readings are displayed with a 0.1 resolution and an accuracy of +/-0.1 pH while the EC and TDS readings are displayed with a 0.01 mS/cm and 1 ppm (mg/L) resolution and 2% full scale accuracy. The EC range of the HI9813-5 is from 0.00 to 4.00 mS/cm and TDS is from 0 to 1999 ppm. The temperature correction coefficient (β) is fixed at 2 %/oC and allows for automatic temperature compensated measurements of EC and TDS.  The HI9813-5 is a basic pH/EC/TDS meter that is calibrated manually to a single point with the use of two trimmers. pH is calibrated to pH 7.01 while EC/TDS is calibrated to either 1.41 mS/cm (1413 µS/cm) or 1500 ppm.  The LCD screen has battery life indicator as well as on-screen tutorial messages. The supplied HI1285-5 probe is a  polypropylene body, amplified pH electrode with a built-in EC/TDS and temperature sensors. The amplifier for the pH electrode prevents interference from humidity and electrical noise from common sources including from motors, ballasts or pumps. The HI9813-5 is a versatile meter for the agricultural, greenhouse and hydroponic uses.