The Rosemount 398 / 398VP TUpH pH and ORP sensors are ideal for measuring pH in harsh process liquids including sour water strippers, pulp bleaching towers using chlorine dioxide, and process streams with organic solvents. TUpH reference technology provides maximum life in processes that typically coat reference junctions.

TUpH junction pores are smaller than typical process particles, preventing plugging. Large surface area maintains steady pH signal even with solids accumulation. Long internal helical diffusion pathway hinders poisoning agents (sulfide, mercury, cyanide, ammonia). ACCUGLASS pH bulb resists cracking with near‑theoretical response at extreme pH. Slotted tip protects glass bulb.

Titanium tube housing, molded Tefzel TUpH construction, choice of Viton or Kalrez seals. Models 398 and 398VP use highest quality materials for superior chemical resistance. Temperature range 0–100°C. SMART enabled. Compatible with all Rosemount Analytical and other manufacturers’ instruments.