Patent ID: 8827983

Claim:
A portable negative pressure wound therapy system, comprising: a dressing assembly for positioning over a wound to apply a negative pressure to the wound; and a canister assembly including: a control unit; a vacuum source disposed in the control unit; a pressure sensor in communication with the control unit; a collection canister including an inlet conduit in fluid communication with the dressing assembly, a chamber to collect wound fluids from the dressing assembly, an inlet port coupled to the inlet conduit to introduce the wound fluids from the dressing assembly into the chamber, and a suction port to communicate with the chamber and the vacuum source; a sensor to detect a condition associated with the collection canister, including: a first electrode including a first portion and a second portion, wherein the first portion of the first electrode is supported by the canister top, and the second portion of the first electrode is configured to extend into the fluid collection chamber; a second electrode including a first portion and a second portion, wherein the first portion of the second electrode is supported by the canister top, and the second portion of the second electrode is configured to extend into the fluid collection chamber; an electric circuit configured to detect an electrical property associated with the first and second electrodes, wherein the second portion of the first and second electrodes is covered with a coating to inhibit encrustation formed by drying of exudate; and an inner chamber disposed within the chamber, the inner chamber bounded by the canister top, an inner wall and a bottom end, wherein the second portion of the first and second electrodes is disposed within the inner chamber, wherein at least a portion of the bottom end of the inner chamber is formed of a water-soluble film.