10
Introduction,
continued
The Platinum Series pH Electrode uses a silver/silver chloride
reference element with a free-flowing junction. When the
dispenser button is pressed, electrolyte gel is dispensed past the
reference element to the reference junction.
The Platinum Series pH Electrode, Model 51910, uses a full
range pH glass that balances speed of response, full range, and
longevity. It is suitable for a wide variety of samples, including
hard-to-measure, pure water samples. If using the sens
ion
System, the meter will automatically account for buffer
temperatures during calibration. The Auto Buffer
Recognition/Auto Temperature Compensation calibration
program built into sens
ion
meters contains accurate pH
profiles for buffers of pH 4.01, 6.86, 7.00, and 10.0 at
temperatures from 0 to 60 °C.
1.2 Electrolyte Description
In a conventional electrode, a frit restricts the release of
electrolyte into the sample. In the Platinum Series electrodes,
the medium viscosity electrolyte gel acts as a restriction device.
Fresh reference electrolyte is supplied from a replaceable
cartridge inside the electrode body by depressing the dispenser
button. By refreshing the electrolyte at the reference junction,
the Hach’s free-flowing reference system eliminates junction
potential errors caused by clogged frits. The gelling agent is
non-ionic and does not interfere with the free flow of ions
across the reference junction. Proper use and care of the
reference half cell extends its life.
1.3 Preparing the Electrode for Use
1.3.1 Assembling the Electrode
New electrodes are shipped with a soaker bottle to keep the
glass bulb hydrated. Remove the electrode from the soaker
bottle and prepare the electrode as follows:
1. Remove the cap from the electrolyte cartridge. Align the
fins on the cartridge with the grooves on the electrode
body. Press the cartridge firmly into the inlet tube of the
