Available for industrial and municipal water treatment operators, SD7000CD and SD7000CD-ORP offer chemically-resistant direct replacement options for Hach®/GLI and Water Analytics/Aquametrix analog 5-wire pH and ORP sensor models. Solution pH is measured differentially with process and inner reference (surrounded by known concentrated pH 7 buffer) electrodes compared to third ground electrode. This minimizes reference junction potential and eliminates sensor ground loop effects.