Hach sc200, User Manual

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10
General Information
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 to
interface with the controller and output a digital signal. Extension cables are required for
connection from the digital gateway to the digital controller. See
Replacement Parts and
Accessories on page 41 .
2.4 Operating Precaution
CAUTION
If the pH process electrode breaks, handle the sensor very carefully to
prevent injury.
Before placing the pH or ORP sensor into operation, remove the protective cap to expose
the process electrode and salt bridge. 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 salt bridge 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. See
Specifications on page 5 for
temperature storage limits.
The process electrode at the tip of the pH sensor has a glass bulb, which can be broken.
Do not subject it 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.