Hach SIGMA 900, Руководство пользователя

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Section 4
Page 29
8837mnt.fm
Humidity Indicator
4.2.2 Replacing Pump Tubing
Note: Do not lubricate the pump
tube with silicone grease, petroleum
jelly, oil, or any other lubricant, as
this will substantially reduce the life
of the pump tube and roller
assembly.
1. To replace the pump tube, remove the four screws on the pump cover.
2. Remove the front cover of the pump housing.
3. Remove the existing tubing. Locate the black dot on the new tubing. The
end of the tube that extends farthest beyond the black dot attaches to the
stainless steel tubing connector.
4. Install the pump tube in the pump housing until the black dots are visible
just outside the pump body.
5. After inserting the new pump tube, reinstall the front cover and secure it
with the four screws until finger tight.
Tubing life will be extended by:
• Locating the sampler as close to the sample source as possible.
• Minimizing the vertical lift (ideally, 15 feet or less).
• Minimizing the number of intake rinses prior to sample collection.
• Rotating the pump tube 90 degrees in the pump housing after
approximately
2 /
3
of the life has been realized (once the tube life has been
determined through use).
• Remove/clean the silicone residue in the interior of the pump housing and
on the rollers before installing a new tube.
4.3 Humidity Indicator
The humidity indicator is located on the left front side of the controller. If the
humidity indicator is blue, the desiccant is dry. If the desiccant turns pink or
white, inspect the electronics housing for seal failure and replace the
desiccant module (Cat. No. 787).
4.4 Desiccant Replacement
To replace the desiccant, remove the controller from the refrigerator cabinet,
and remove the screws from the controller bottom flange. Remove the
desiccant bag and replace it with a new one. Replace the controller gasket
and cover plate. Reattach the controller to the refrigerator.
4.5 Refrigerated Compartment Thermal Control System Calibration
To verify the correctness of the refrigerator compartment temperature which is
indicated on the sampler controller display, place a laboratory grade
thermometer into a beaker with 150 mL water into the right rear corner of the
refrigerated compartment - and then close the refrigerator compartment door.
Allow the refrigerator to run for 2-3 hours. This will assure equilibrium
between the temperature in the compartment and the water in the beaker.
Compare the temperature readout on the display with the temperature
indicated on the thermometer. If the readings do not agree, it is necessary to
calibrate the Reference Temperature Sensor. This cylindrical shaped sensor