Hach Flo-Dar, Basic User Manual

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C A U T I O N
Radar RF exposure hazard. Avoid putting the head and other vital organ areas within the microwave
beam (within 1 meter (3.3 ft) of the microwave aperture). Although the Flo-Dar microwave power level
is very small (approximately 15 mW) and is well below government stated exposure limits for
uncontrolled environments, users of this product should obey proper safety protocols for the handling
of devices with radar frequency transmitters.
N O T I C E
Handle the sensor with care to prevent damage to the microwave transmitter. Damaged transmitters can result in
higher signal power levels, which can interfere with essential terrestrial microwave links.
The safety of the transmitter may be impaired if any of the following conditions have occurred:
• Visible damage
• Storage above 70 °C for prolonged periods
• Exposure to severe transport stresses
• Previous installation
• Failure to operate properly
If any of these conditions have occurred, return the device to the manufacturer for recertification.
7.1 Look for corrosion and damage
Look for corrosion and damage once a year.
Note: The only parts of the Flo-Dar system that can be replaced by the user are the bail assembly and the cable. If
the sensor becomes defective, it must be replaced as a complete unit.
1. Look for corrosion or damage that can let environmental gases into the interior of the sensor.
2. Make sure that no swelling, blistering, pitting or loss of material has occurred on the upper and
lower portions of the main plastic enclosure, the depth module or the radome.
3. If the extended range sensor is used, examine the enclosure and the four ¼-20 stainless steel
bolts.
4. If the surcharge velocity sensor (SVS) is used:
a. Make sure that the unit is not corroded and the labels can be read.
b. Examine the connectors for any damage or corrosion. Tighten all the connectors in the
system.
5. Examine the connectors for any damage or corrosion. Tighten all the connectors in the system.
6. If corrosion is found on the connectors, clean and dry the connectors to make sure that no
moisture is on the connector pins. If corrosion is severe, replace the cables. Refer to
Replace a
cable on page 27.
7.2 Clean the instrument
D A N G E R
Explosion hazard. Never attempt to wipe or clean the Flo-Dar or SVS sensor while in a hazardous
location. Do not use abrasives or high-pressure hoses or washers to clean the sensors. Do not disturb
the pressure port on the bottom of the sensor.
Regular cleaning is not necessary because the sensor does not contact the flow unless a surcharge
condition occurs. Examine the sensor after a surcharge to see if cleaning is necessary.
Item to collect: Retrieval pole with hook (optional)
1. Remove power to the sensor.
2. Put the hook on the retrieval pole to remove the sensor without manhole entry. Make sure the
grounding strap is on the pole.
26 English