The basic system of one or two sensors connected to an indicating transmitter (DTR) is the same for all PR‑23 in-line refractometer models. However, there are different sensor models, each model is adapted for different process requirements.
The models PR‑23‑AC and PR‑23‑AP meet the 3‑A Sanitary Standard requirements. With an ATEX approved PR‑23‑…‑AX sensor or an FM approved PR‑23‑…‑FM sensor or a CSA approved PR‑23‑…‑CS sensor or a Nepsi certified PR‑23‑…‑CX sensor or an LLC Certification Center VELES approved PR‑23‑…‑RX sensor, a process refractometer system can be used in potentially explosive atmosphere. Intrinsically safe process refractometer PR‑23‑…‑IA/‑IF/‑CI/‑JI/‑RI can be used in hazardous locations in Zone 0 and Zone 1. The Safe‑Drive system with a PR‑23‑SD sensor enables safe sensor insertion and removal also when process line is in full operation.