US 11,719,666 B2
System comprising pH/ORP electrodes with improved anti-poisoning characteristics
Benjamin Carr, Stroud (GB); and Kenton Knight, Gloucester (GB)
Assigned to ABB Schweiz AG, Baden (CH)
Filed by ABB Schweiz AG, Baden (CH)
Filed on Sep. 18, 2020, as Appl. No. 17/24,722.
Claims priority of application No. 19198439 (EP), filed on Sep. 19, 2019.
Prior Publication US 2021/0088466 A1, Mar. 25, 2021
Int. Cl. G01N 27/403 (2006.01); G01N 27/30 (2006.01)
CPC G01N 27/301 (2013.01) [G01N 27/302 (2013.01); G01N 27/4035 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A reference electrode system for a pH-sensor system, the reference electrode system comprising:
a first junction comprising a membrane with a sealed side;
a reference electrode, comprising a top end portion and a bottom end portion, wherein the reference electrode and/or an electrically conducting wire of the reference electrode is covered completely, except for the bottom end portion of the reference electrode, by a sleeve and wherein the top end portion and/or the electrically conducting wire protrudes from the sleeve; and
a tube, having an open top end portion and a closed bottom end, the tube being arranged, at least partly, around the reference electrode, the electrically conducting wire, and the sleeve, the closed bottom end of the tube being arranged near the end of the bottom portion of the reference electrode;
wherein the closed end of the tube prevents ions from penetrating therethrough.