Chemtrac Auto Clean UV254, Руководство пользователя, Страница: 26 / 41

Chemtrac UV254 Monitor
– UVM5000 v 2.1
Chemtrac, Inc. 25
12 Slope Correlation Method
The following method can be used to correlate the UV254 data to the parameter of choice such as TOC, COD,
etc. Note that for many applications the absorbance reading of the UVM5000 can correlate very well with
standard water quality parameters.
1. Make sure the main display screen shows the UV absorbance (UVA) value of the water currently flowing
through the monitor. Record the UVA value (UVA Value).
2. Immediately after recording the displayed value, take a water sample.
3. Using a lab or a portable test instrument, determine the value of the desired water quality parameter (factor
programmed to COD, TOC, DOC, BOD, Color, etc.) for the water sample (Lab Value).
4. The relationship between the UVA value and the desired water
quality parameter can then be determined using the formula on
the right.
5. Alternatively, the slope can be determined via multiple test points over the expected testing range of the
monitor. In this case, the slope can be calculated simply using a spreadsheet package (such as Microsoft
Excel) to plot a best fit line through several test points.
6. Once the slope (correlation factor) has been determined,
enter it in the “Slope 1:” field within the Crltn. Calculation
menu. The default value is 100 and the range is from 0 to
500.
7. Expand the +UVT/UVA mode menu, scroll down to Crltn mode and select it.
8. A value for the water parameter is now displayed on the
main display page.
9. The slope can be re-determined using the above steps as
necessary.
Note: Monitors with Dual Feed option use two correlation factors (Slope 1 for stream 1 and Slope 2 for stream
2).