C O N T E N T S Warranty ....................i Introduction ..................1 Getting Started ..................1 Initial Inspection ..............1 Battery Installation ..............1 Key Pad ..................2 Connecting the Sensor and Cable ........3 Membrane Installation ............5 Run Screen ................6 Backlight .................7 Powering Off ................7 Navigation ................7 First Power On ................8 System Setup Menu ................9...
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Calibration ..................17 Temperature .................17 Barometer ................17 Dissolved Oxygen ..............17 Salinity Compensation Calibration ........21 Taking Measurements ...............22 Saving and Viewing Data ..............23 Saving Data ................23 Viewing and Erasing Saved Data – Data Mode ....23 Principles of Operation ..............25 Care, Maintenance and Storage ............26 General Maintenance ............26 Sensor Maintenance ............28 Sensor Storage ..............32...
W A R R A N T Y The YSI Pro20/Pro20i instrument is warranted for three (3) years from date of purchase by the end user against defects in materials and workmanship, exclusive of batteries and any damage caused by defective batteries.
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PRODUCT COVERED BY THIS WARRANTY. IN NO EVENT SHALL YSI BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES RESULTING FROM ANY DEFECTIVE PRODUCT COVERED BY THIS WARRANTY.
67) case, backlit display, user-selectable sensor options, internal barometer, and a rugged, rubber over-mold case. The Pro20/Pro20i can not communicate to a PC via a Pro Plus communications saddle. Connecting the Pro20/Pro20i to a communication saddle may cause erratic instrument behavior.
5. Place the battery cover on the back of the instrument and tighten the four screws. Do not over-tighten. Figure 1. Pro20/Pro20i with battery cover removed. Notice battery symbols indicating polarities. The waterproof instrument case is sealed at the factory and is not to be opened, except by factory-authorized service technicians.
Number Description Calibrate Press and hold for 3 seconds to calibrate. Initiates One Touch Calibration. Opens Calibrate menu from the run screen if One Touch Calibration is disabled. Up Arrow Use to navigate through menus, to navigate through box options along the bottom of the Run screen, and to increase numerical inputs.
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The Pro20/Pro20i has two compatible sensors for use with a field cable: Polarographic – This sensor has a black sensor body and is engraved with the model number 2003. Polarographic will be abbreviated Polaro in the instrument’s menu. Galvanic – This sensor has a grey sensor body and is engraved with the model number 2002.
Connecting the Cable (Pro20 Only) The Pro20 is designed for field and laboratory use. It is compatible with two different cable options: 1. The field rugged cable is available in standard lengths of 1, 4, 10, 20, 30, and 100 meters with special lengths available between 30 and 100 meters.
Run screen (figure 5). The first time the Pro20/Pro20i is turned on, it will step through language, sensor, and membrane selections; see the First Power On section of this manual for more information.
NAVIGATION The up and down arrow keys allow you to navigate through the functions of the Pro20/Pro20i. Navigating the Run Screen When in the Run screen, the up and down arrow keys will move the highlighted box along the bottom options. Once a box is highlighted, press enter to access the highlighted option.
Navigating the System Setup Menu When in the System Setup menu, the up and down arrow keys will move the highlighted bar up and down the system setup options. See the System Setup menu section of this manual for more information about these options.
When enabled, the DO%L calibration value is always 100% regardless of the altitude or barometric pressure of the location. This deviates from YSI’s traditional method of expressing DO% saturation where the % calibration value decreases with a decrease in barometric pressure, i.e.
Example: 750/760 = 0.9868 x 100 = 98.68% calibration value when DO Local is disabled. When DO Local% is enabled, the Pro20/Pro20i corrects for barometric pressure for each DO measurement instead of during calibration. Example: Instrument #1 with DO Local% enabled: At 737 mmHg barometric pressure, roughly 841 ft above sea level, the instrument would calibrate to 100%.
‘X’ in the box next to Audio. When Audio is enabled, the Pro20/Pro20i will beep twice to indicate stability when Auto Stable is enabled. The instrument will also beep when a key is pressed. When Audio is disabled, the Pro20/Pro20i will not beep. CONTRAST To adjust the display Contrast, use the up or down arrow keys to highlight Contrast, then press enter.
If using a ProBOD sensor/cable assembly, the sensor type should be set to polarographic. The Pro20/Pro20i has two compatible sensors for use with a field cable: • Polarographic – This sensor has a black sensor body and is engraved with the model number 2003.
enabled membrane type will have an ‘X’ in the box next to it. Use the down arrow key to highlight the ESC – Exit box and press enter to save changes and to close the membrane submenu. The dissolved oxygen sensor is supplied with membranes specific to the sensor type and are color coded as described in the following tables.
any changes, highlight the ESC-Exit box and press enter to close the Auto Stable submenu. To disable Auto Stable, set the DO% Change input to 0.0. When Auto Stable is enabled, an symbol will display next to the dissolved oxygen value on the run screen and blink during stabilization. When the dissolved oxygen value has stabilized based on the Auto Stable settings, the will display steadily and the instrument will...
Highlight Yes and press enter to continue with the reset or highlight No and press enter to cancel the reset. A Factory Reset will not affect data saved in the instrument’s memory. The following will be set in the Pro20/Pro20i after performing a reset:...
Parameter Reset Defaults Temperature Units Dissolved Oxygen Units mg/L and % Pressure Units mmHg Dissolved Oxygen Sensor Type Last Setting Confirmed Membrane Type Last Setting Confirmed Salinity Compensation Value 0.0 ppt DO Local% One Touch Cal Display Contrast Set to mid range Auto Shutoff 30 minutes Auto Stable...
DISSOLVED OXYGEN The Pro20/Pro20i can be easily calibrated with the press of one key by enabling One Touch Cal in the System Setup menu and following the One Touch Calibration procedure.
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It is not necessary to calibrate in both % and mg/L or ppm. Calibrating in % will simultaneously calibrate mg/L and ppm and vice versa. YSI recommends calibrating dissolved oxygen in % for both ease and accuracy. ONE TOUCH CALIBRATION Perform this calibration procedure when One Touch Cal is enabled in the System Setup menu.
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Press and hold the Calibrate key for 3 seconds. Highlight % and press enter . The Pro20/Pro20i will display the current DO% and temperature readings along with the % calibration value. The % calibration value is based on the barometer reading.
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Press and hold the Calibrate key for 3 seconds. %Local will be automatically highlighted, press enter . The Pro20/Pro20i will display the current DO% and temperature readings along with the % calibration value. The % calibration value will always be 100% for DO Local%.
See the Troubleshooting guide for possible solutions. SALINITY COMPENSATION CALIBRATION The Pro20/Pro20i uses a user inputted salinity value in ppt (parts per thousands) to compensate dissolved oxygen mg/L values. The salinity compensation value entered in the Pro20/Pro20i should be the salinity value of the water you are testing.
Figure 10, Salinity box highlighted T A K I N G M E A S U R E M E N T S Before taking measurements, be sure the instrument has been calibrated to ensure the most accurate readings. Turn the instrument on and wait 5-15 minutes if using a polarographic sensor.
Each data point is referenced with a data set number, 01 through 50. The Pro20/Pro20i can not communicate to a PC via a Pro Plus communications saddle. Connecting the Pro20/Pro20i to a communication saddle may cause erratic instrument behavior.
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Figure 12, Data mode. Viewing Data Once in data mode, use the up and down arrow keys to view saved data sets in sequential order or press enter to access the bottom functions. After accessing the bottom functions, highlight the Data box and press enter to regain access to viewing data.
12 is erased then 13 becomes 12, 14 becomes 13, and 15 becomes 14. The instrument will return to data mode after erasing one data set. Select Erase All Data Sets and press enter to clear the Pro20/Pro20i memory and return to data mode. Exiting Data Mode While in Data mode, press enter to access the bottom functions.
zero. Hence, the amount of oxygen diffusing through the membrane is proportional to the absolute pressure of oxygen outside the membrane. If the oxygen pressure increases, more oxygen diffuses through the membrane and more current flows through the sensor. A lower pressure results in less current.
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equivalent lint-free cloth. Alcohol can be used to clean the plastic parts, but use only water and mild detergent on the o-ring itself. Also, inspect the o-rings for nicks and imperfections. Using alcohol on o-rings may cause a loss of elasticity and may promote cracking.
If the connector is corroded, contact YSI Technical Support or the Authorized dealer where you purchased the instrument. Remove sensors upside down (facing the ground) to help prevent water from entering the port upon removal. SENSOR MAINTENANCE Sensor Maintenance - Temperature You must keep the temperature portion of the sensor free of build up.
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Do not sand the electrode every membrane change as this is not routine maintenance. In fact, visually, the anode may appear tarnished and operate just fine. YSI recommends using the 400 grit wet/dry sanding disks after a membrane change if the sensor has...
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Rinse thoroughly and wipe the gold cathode with a wet paper towel before putting on a new membrane cap. If the cathode remains tarnished, contact YSI Technical Support or the Authorized dealer where you purchased the instrument.
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Not adhering to either of these instructions can damage the electrodes. If this procedure is unsuccessful, as indicated by improper sensor performance, contact YSI Technical Support or the Authorized dealer where you purchased the instrument. Galvanic Sensors – Model # 605202...
The color change is acceptable and normal as long as DO readings remain stable. At the time the membrane cap is changed, YSI recommends that you rinse the anode (silver shaft of the sensor) with purified water and wipe with a clean paper towel.
to air dry completely. Use a clean, dry new membrane cap to screw over the sensor to keep it dry and to protect the anode and cathode. After storing the sensor for a long period of time it is necessary to “condition”...
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Symptom Possible Solution Instrument readings Verify correct sensor/membrane type are inaccurate. selection in the System Setup menu. Verify calibration, barometer reading, and salinity settings are correct and recalibrate. Verify accurate temperature readings. Sample temperature is over 45 ºC, the temperature compensation range. Probe may not have been in 100% water saturated air during calibration procedure.
S P E C I F I C A T I O N S These specifications represent typical performance and are subject to change without notice. For the latest product specification information, please visit YSI’s website at ysi.com or contact YSI Tech Support. Parameter Range...
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607125 Pro20i instrument with integral (i.e. built-in) 4-meter cable. Polarographic DO sensor included. 60520-1, -4, -10, 1, 4, 10, 20, or 30-meter cable for Pro20 instruments; -20, or -30* with temperature and a port for Dissolved Oxygen 605202 Galvanic Dissolved Oxygen sensor; 5913 membrane...
YSI’s recycling program ensures that old equipment is processed in an environmentally friendly way, reducing the amount of materials going to landfills.
800-897-4151 (+1 937-767-7241). When returning a product for service, include the Product Return form with cleaning certification. The form must be completely filled out for a YSI Service Center to accept the instrument for service. The form may be downloaded from www.ysi.com.
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