Hach NT3100sc, User Manual

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1. Disconnect the equipment from its power source to verify that it is or is not the source of the
interference.
2. If the equipment is connected to the same outlet as the device experiencing interference, connect
the equipment to a different outlet.
3. Move the equipment away from the device receiving the interference.
4. Reposition the receiving antenna for the device receiving the interference.
5. Try combinations of the above.
2.2 Icons used in illustrations
Manufacturer supplied
parts
Mandatory action Do not use tools
Do steps in reverse
order
Do one of these
options
2.3 Intended use
The NT3100sc and NT3200sc probes are intended for use by water treatment professionals to make
sure that there is a consistently-low level of nitrate and nitrite in the municipal sewage at treatment
plants, surface water, untreated water and treated drinking water. Low nitrate and nitrite levels
prevent water toxicity exposure and/or make sure of regulatory compliance.
2.4 Theory of operation
Nitrate dissolved in water absorbs UV light with wavelengths below 250 nm. The nitrate and nitrite
absorption of UV light makes it possible to photometrically determine the dissolved nitrate and nitrite
concentrations without reagents. The sensor is put directly in the medium. The color of the medium
does not have an effect on the measurement because the measuring principle is based on the
analysis of invisible UV light.
2.5 Product overview
Use the NT3100sc probe to measure nitrate concentrations and the NT3200sc probe to measure
nitrate and nitrite concentrations. Refer to
Figure 1 .
Use the probe in activated sludge tanks in municipal sewage treatment plants, surface water,
untreated water and treated drinking water, or the outlet of wastewater treatment plants. Pumping
and conditioning are not necessary. Put the probe directly into the medium.
Note: Use the flow through unit when direct measurement in the medium is not possible or it is necessary to
measure a filtered sample (e.g., very high TSS
3
content, sewage treatment plant inlet or waste dump leachate).
Connect the probe to an SC Controller for power, operation, data collection, data transmission and
diagnostics. Refer to the SC Controller manual for an overview of the controller.
The probe has a beam absorption photometer with turbidity compensation. A built-in wiper
mechanically cleans the measuring window.
Note: Enable the sludge mode to increase the number of concentration measurements done when the probe
measures in activated sludge. When sludge mode is active, several measurements are done to compensate for the
different sludge compositions.
Dissolved nitrate and nitrite, dissolved organics and particles absorb light, which has an effect on the
measurement absorbance value. The probe adjusts for this turbidity interference. However, there
may be applications where the combination of these compounds absorbs too much light. Thus, there
is not sufficient light transmitted to the sensors and inaccurate measurements occur. Make sure to
select the probe with the correct pathlength. Refer to
Table 1 and Table 2 .
3
The TSS value is a recommendation and based on the substances of the wastewater.
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