... environmental protection, sewage treatment, thermal power, breeding, food processing, printing, metallurgy, pharmacy, fermentation, chemical industry, water and other solution ... 10A 220VAC11.Working conditions: environmental temperature is 0 ~ 60°C, relative humidity is 90% or less12.Input impedance: ... High accuracy online PH controller/PH probe/water treatment PH analyzer with signal output 4-20mA