Hach Flo-Dar, Руководство пользователя

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33
Maintenance
5.3 Cable replacement
Procedure
1. Disconnect power to the sensor at the logger or controller.
2. Put the hook on the retrieval pole for removal without manhole entry. Make sure the
grounding strap is on the pole.
3. Hook the bail on the sensor and turn the pole counter-clockwise to unlock the sensor
from the frame. Remove the sensor.
4. Remove the cable clamp by removing the two Phillips screws on the sensor handle.
Remove the cable.
5. Install the new cable. Make sure that the connector is aligned properly and that no
debris or water gets into the connector.
6. Replace the cable clamp.
7. Lower and position the sensor on the frame. Make sure that the cable points toward
the center of the manhole.
8. Turn the retrieval pole clockwise to engage the locking bars into the frame.
9. Apply power to the sensor via the logger or controller.
5.4 Changing the sensor dessicant
The desiccant canister contains beads of silica gel which ensure proper operation of the
pressure transducer located in the Flo-Dar Sensor. When the beads are yellow, they can
absorb moisture from the air. When they are green, they are saturated and cannot absorb
any more moisture from the air, and they must be replaced immediately.
The cable assembly with desiccant hub is compatible with either the Flo-Logger or the
FL900 loggers. When using this cable assembly with the Flo-Logger, do not disconnect
the desiccant cartridge that is attached to the Flo-Logger itself.
Important Note: When the beads begin to turn green, replace or rejuvenate the beads.
Permanent damage to the sensor may occur if the desiccant is not maintained. Never
operate the sensor without the proper desiccant. When rejuvenating beads, remove them
from the canister and heat at 100-180 ºC (212-350 ºF) until the beads turn yellow. If the
beads do not turn yellow, replace them with new beads. Do not head the canister.
5.4.1 Desiccant replacement procedure
Note: Replacing the desiccant does not require that the desiccant container be removed from the
desiccant box.
1. Use a slight twisting motion to twist the bottom end-cap until its slots align with the
retaining clips (
Figure 18 on page 34 ).
2. Gently remove the end cap by grasping it and pulling it straight out.
3. Pour the desiccant beads out of the canister.
4. Hold the canister up to the light and inspect the hydrophobic filter.
• If you see a small, dim light spot while looking through the hole, the filter is in good
condition. If you see a bright light spot, the filter is probably torn. Replace the filter.
• If the desiccant beads were completely saturated with water or the filter has saturated
with water or grease, replace the filter.