ORP standard solutions allow you to test the precision of ORP electrodes. For example, by immersing the electrode in HI 7020 solution, you should read within the 200 to 275 mV range (@20°C/68°F).
If the reading is outside the indicated interval, clean and condition your ORP electrode in HANNA® pretreatment solution. Use HI 7092 for oxidizing or HI 7091 for reducing pretreatment.
HI98130 COMBO Tester for pH/EC/TDS/C° up to 20 mS, waterproof
HI7031L - EC 1413 µS/cm@25°C - 500ml
HI706 Checker HC ® - Phosphorous, HR
HI716 Checker HC ® - Bromine
สารละลายมาตรฐานความขุ่น 20 NTU
HI5009 - 9.00 pH@25°C - TQ - 500ml 


