Hach 6120118 - Manual (Page 9)

9
General Information
Figure 3 Insertion Style Sensor with Domed Electrode
Figure 4 Sanitary-style Sensor
2.3 The Digital Gateway
The digital gateway was developed to provide a means to use existing analog sensors with
the new digital controllers. The gateway contains all the necessary software and hardware
to interface with the controller and output a digital signal.
2.4 Operating Precaution
Before placing the pH or ORP sensor into operation, remove the protective cap to expose
the process electrode and reference junction. Save the protective cap for future use.
For short-term storage (when sensor is out of the process for more than one hour), fill the
protective cap with pH 4 buffer or DI water and place the cap back on the sensor. Keeping
the process electrode and reference junction moist will avoid slow response when the
sensor is placed back in operation.
For extended storage, repeat the short-term storage procedure every 2 to 4 weeks,
depending on the surrounding environmental conditions.
CAUTION
If the pH process electrode breaks, handle the sensor very carefully to
prevent injury.
The process electrode at the pH sensor tip has a glass bulb, which can break. Do not
subject this electrode to abrupt impact or other mechanical abuse.
The gold or platinum process electrode at the ORP sensor tip has a glass shank (hidden
by the salt bridge) which can break. Do not subject this electrode to impact or other
mechanical abuse.
22.2 mm (0.875 inches)
149.9 mm (5.9 inches)
22.2 mm (0.875 inches)
187.3 mm (7.37 inches)
88.9 mm (3.5 inches)
22 mm (0.87 inches)
49.1 mm (1.96 inches)