HI72911D

Description

The HI72911D is a titanium body, polymer filled, double reference junction pH electrode with a DIN connector. This flat tip sensing portion of this electrode is made with general purpose glass. The HI72911D also has a PTFE type junction along with a built-in temperature sensor and amplifier within a single probe design. This design consideration is ideal for measuring the pH in boilers and cooling towers. The HI72911D is designed for use with Hanna’s HI99141 pH meter.

•  Built-In Temperature Sensor
•  Recessed, Flat Tip
•  Titanium Body

  The HI72911D uses general purpose (GP) glass, flat tip bulb, titanium body, and PTFE junction with polymer electrolyte.
General Purpose Glass Formulation
•  The measurement of pH at very high temperatures is detrimental to the sensitive glass bulb and will shorten the life of it.
•  A pH electrode with general purpose (GP) glass will have a resistance of 100 megaohms at 25^°C while the resistance of LT glass is around 50 megaohms at 25^°C.
•  As the temperature of the glass decreases in the sample, the resistance of the LT glass will approach that of GP glass.
•  If using GP glass, the resistance would increase above the optimum range, resulting in increased impedance and ultimately affecting the measurement.
•  The HI72911D is suitable to use with samples that measure from 0 to 80^°C.

  Flat Tip Bulb
•  The recessed flat tip bulb of the HI72911D is easy to clean and prevents solids in solutions from collecting on the sensor.
•  Other tip shapes include conic for penetration and spheric for aqueous measurements.

  Titanium Body
•  A titanium body increases immunity to electrostatic and magnetic fields.
•  It also allows for strong corrosion resistance, even in seawater.

  Matching Pin
•  A matching pin is a differential measurement technique used to eliminate ground loops and common mode perturbations for the measurement system.
•  In a system without a matching pin, electrical currents in the sample can affect the reference half cell voltage that is connected via the liquid junction with the sample.
•  In this case, the reference electrode picks up the electromagnetic fields and the measurement of the pH is altered.
•  The matching pin isolates these current/magnetic fields from the reference electrode.
•  The HI72911D titanium body serves as a matching pin for safe precise pH measurements.

  PTFE Junction
•  Porous polytetrafluoroethylene (PTFE) is a hydrophobic material that is available with different porosities.
•  This type of junction is often used on electrodes with polymer electrolytes. Because of its chemical advantages, PTFE is widely used in industrial applications.

  DIN Connector
•  The HI72911D uses a DIN connector.
•  This type of connector is generally proprietary to the meters they are supplied with and may not be interchangeable.
•  The HI72911D is designed for use with Hanna’s HI99141 pH meter.
•  Other type of connectors include BNC, screw type, T-type, and 3.5mm to name a few.

     SPECIFICATIONS