Electrodes with glass membranes - series 21

glass electrode

The glass membranes of these electrodes are made of suitable sensitive glass. Lenght of the body of electrode is 150mm. The connection of the sensitive membrane with coaxial cable is realized by a liquid contact. Coaxial cable is normally ended by BNC connector but we can also replace it by another connector i.e. german DIN. The body of the electrode is made of low leach glass with higher chemical resistance and is screened by a metal foil.

Table of the pH and sodium electrodes parametres

Electrode Type Temp. 
range [°C]
resist. [MOhm]*
Conc. range [mol/l] Recom. ref. 
Max. electrolyte 
leakage [ul/h]
pH 01-21 0-80 200 100 - 10-14 RCE 101 x
sodium 11-21 0-80 150 10-1 - 10-6 RAE 102 x
pH 01-21RX 0-80 200 100 - 10-14 RRE 131RX x
pH combined 01-29 0-80 200 100 - 10-14 x 10
pH combined, low resistance 01-29LR 0-80 < 50 100 - 10-13 x 10
pH small bulb 01-32 0-80 500 100 - 10-14 x 10
pH spear-tip 01-33 0-80 500 100 - 10-12 x 10
pH big spear 01-34 0-80 200 100 - 10-12 x 10
pH flat membrane 01-36 0-80 500 100 - 10-12 x 10
pH combined 01-29RX 0-80 200 100 - 10-14 x 10
pH spear-tip 01-33RX 0-80 500 100 - 10-12 x 10
sodium combined 11-29 0-80 150 10-1 - 10-6 x 10

* - maximal electrical resistance at 25 deg. C

pH combined electrodes - series 29

combined electrode

The electrodes have glass membranes and incorporated external reference system. The connection of the glass membrane with coaxial cable is carried through a liquid contact. Coaxial cable is typically ended by BNC connector. The external Ag/AgCl reference system is incorporated in the outer part of the body of electrode. The external reference electrode is filled by 1 M KCl. The electrode body is made of a low leach glass with high chemical resistance against the majority of normally used chemicals. Typical length of body is 145mm.

pH combined electrodes with a small bulb - series 32

ph combined electrode, small bulb

These types of electrodes are produced with a small bulb with a diameter of 6mm. They are suitable for pH determination in a small volume of samples. The reference ceramic junction is near the bulb.

pH spear-tip combined electrodes - series 33

ph spear-tip electrode

The measuring part of the electrodes is spear-like shaped. In a close proximity of this spear there is an exit of external reference Ag/AgCl electrode. The electrodes are used for pH-measurements in soft materials (as cheese and meat).

pH combined big spear-tip electrodes - series 34

combined ph electrode, spear tip

The measuring part of the electrodes is spear-like shaped with a diameter about of 12mm. In a close proximity of this spear there is an output of external reference Ag/AgCl electrode. The electrodes are used for pH measurements in agriculture.

pH combined flat membrane electrodes - series 36

combined ph electrode, flat membrane

The glass membrane is created by flat glass membrane with a diameter about of 6mm. The electrodes are used in pH determination of wet paper or skin.

Electrodes with added designation MR

These electrodes have a strike resistant bulb created by membrane with thick wall.

Electrodes with added designation P

ph combined electrode with epoxy body

These electrodes have a epoxy plastic body. The glass membrane is protected by a plastic wall. The epoxy body exhibits good resistance not only towards acids and bases, but also towards common organic solvents like acetone.

pH electrodes with added designation PV

electrodes in PVC body

These pH electrodes have PVC body. The glass bulb is protected by wall made of this plastic. PVC is resistant to mineral acids and bases. The construction is primarily intended to measuring in water solutions. Significant benefit is the low price.

Electrodes with added designation HP

These electrodes have a glass membrane created by special glass suitable for measuring pH in alkaline region.

Electrodes with added RX index

The RedoX inner reference system is used as a reference system. The adventage of these electrodes consists in a better behaviour during temperature changes.

Electrodes with added LR index

These pH electrodes have extra low electrical resistance. They are suitable for measuring in low temperatures (less than 10 deg. of C.).

Electrodes with added designation BJ

These are glass combined electrodes. The BNC connector is mounted in the head of the electrode.

Electrodes with added designation RCE

These are pH combined electrodes with an external saturated calomel reference system. The electrodes have a high potential stability of the reference system.

Other dimensions of electrodes

All types of glass electrodes we can make in another lengths than standard lengths figured here.

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