HI3131B

Description

The HI3131B is a glass body, refillable, single junction ORP electrode with a BNC connector. This electrode has a single ceramic junction as part of the reference cell and a platinum ORP sensing pin. This design consideration is ideal for laboratories and general purpose ORP measurements, as well as for use as an indicating electrode in ORP titrations.

•  Platinum Pin
•  Refillable Electrode
•  Single Ceramic Junction

 The HI3131B uses a platinum pin, glass body, single ceramic junction and is refillable with 3.5M KCl + AgCl.
Platinum Sensing Pin
•  The HI3131B ORP sensor is made with platinum. An ORP sensor must be chemically inert; it cannot be oxidized or reduced itself.
•  It must also have the proper surface characteristics to promote rapid electron exchange, a property known as high exchange current density.
•  Two noble metals have proven to work well for this purpose: pure platinum and pure gold are both used in the construction of ORP sensors.
•  The platinum sensor is often preferred because it is mechanically simpler and safer to produce.
•  Platinum can be welded to glass and has the same thermal coefficient.
•  The platinum sensor signal is carried through the electrode body, and together with the reference signal is conducted to the measurement meter.

  Glass Body
•  The glass body is ideal for laboratory use.
•  The glass is resistant to many harsh chemicals and is easily cleaned.
•  The glass body also allows for a fast transfer of heat to the internal reference electrolyte.
•  The mV generated by the reference cell is temperature dependent.
•  The faster the electrode reaches equilibrium, the steadier the reference potential.

  Single Ceramic Junction
•  The outer junction of an electrode, also known as a salt bridge, is necessary component of the electrical circuit.
•  The movement of ions must flow through the junction for a steady reading. The outer reference has a single ceramic frit.
•  The ceramic is a porous material that is easily fused with the glass body and has a similar expansion coefficient.
•  A single ceramic junction has a flow rate of 15-20 μL/hour.
•  Other junction types are available with higher flow rates and made with different materials.

  Refillable
•  The HI3131B is a refillable probe.
•  Since it is a single junction ORP electrode the fill solution is the HI7071 3.5M KCl + AgCl.
•  If using a refillable ORP electrode, the fill cap should be removed prior to measurement.
•  Removing the cap creates positive head pressure in the reference cell allowing for higher flow rate of electrolyte through the outer junction.
•  A higher flow rate will result in a faster and more stable reading.

  BNC Connector
•  The HI3131B uses a BNC connector.
•  This type of connector is universal in that it can be used on any pH meter that has the female BNC probe input.
•  Other type of connectors include DIN, screw type, T-type, and 3.5mm to name a few.
•  These types of connectors tend to be proprietary for a particular type of meter and are not interchangeable.

     SPECIFICATIONS