10-AU Calibration 3 Main Steps A) Setting the basic operating level B) Blanking the instrument C) Calibration with a known concentration standard

Keypad Display Power in;Data out Exhaust Intake Necessary Equipment and Supplies Allen wrench

Calibration Definitions Basic Operating Level - The Sensitivity level is set to establish the Fluorometers operating range. Ranges - 3 ranges (Low, Medium, High), each a factor of 10 more sensitive than the next, providing a direct fluorescence readout value of The Low range gives the highest sensitivity for reading the lower concentrations. Auto-ranging - will select a range that gives a reading between 8 to 95 % FS for best resolution. FS % - Full Scale percentage, each range can read up to 100 % FS. Above that will give an "OVER" reading on the Home screen and the next highest range should be used. If the High Range still reads "OVER" then first try reducing the Sensitivity using the Span adjustment. Full scale value - The maximum concentration level or raw fluorescence value that can be read on each of the 3 ranges at the current Span setting. The Full Scale settings for the current calibration can be viewed by pressing the Back Arrow at the Home screen. Span % - Used as a Fine Adjustment for the sensitivity level during the calibration process. TC - Time Constant settings that are user-settable to 1, 2, 4 or 8 seconds. The higher the value, the slower the response time, so the variation in the readings will be reduced, resulting in a smoothing effect on the readings.

Table 1. Concentration Ranges and % Full Scale settings for Rhodamine and Chlorophyll a Calibration Standards

Setting the Basic Operating Level To be performed the 1 st time you use the instrument, or any time you switch to a different application. 1. Turn on the 10AU and allow the instrument to warm up for at least 10 minutes. 2. Using Table 1, determine the appropriate range and %FS for your calibration standard.

Setting the Basic Operating Level – con’t 3. Access screen 2.4 and set range control to manual and range to the appropriate level for your standard.

Setting the Basic Operating Level – con’t 4. Access Screen Loosen the sensitivity locking screw using allen wrench. 6. Insert and cover your standard. Sensitivity locking screw

Setting the Basic Operating Level – con’t 7. Using the sensitivity knob slowly turn the knob to adjust the %FS to the value appropriate for your standard’s concentration (See Table 1). A deviation  5% is acceptable. 8. When the %FS reaches the designated value, tighten the sensitivity locking screw. 9. The Basic Operating Level is now set. Note down the High Volt value at Screen 3.1 for Future Reference. Sensitivity Knob

Preparing for the Calibration 2. Access screen Press to access screen 2.6 and Reset the Calibration to Default settings. Return to screen Determine if Sample Temperature Compensation is required. Refer to Appendix 6 of the User Manual for details. The Temperature settings at Screen 1.7 are required before calibrating.

Blanking the Instrument 1. Access screen Insert your blank and press 1 to Run blank. You can choose to have the 10-AU subtract the blank signal from the sample readings.

Calibration with Your Standard 1. Access screen Press to access screen 2.2 and input the actual concentration of your standard. Return to screen 2.0

Calibration with Your Standard con’t 3. Insert your standard and press 3 to run standard. The following screen will show the highest concentrations readable on each range setting. You can use the arrow keys to adjust the span level (fine sensitivity adjustment) to change these Full Scale concentration values. This is not required unless you like each range to end at a specific concentration. It is a personal choice. Press the key and the calibration point is set.

Calibration with Your Standard con’t 4. Access Screen 2.4 again and return range control to automatic. 5. The Calibration is now complete. You can start reading your samples on the 10-AU.