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Using the LI-870 O Analyzer LI-COR Biosciences 4647 Superior Street Lincoln, Nebraska 68504 Phone: +1-402-467-3576 Toll free: 800-447-3576 (U.S. and Canada) envsales@licor.com Regional Offices LI-COR Biosciences GmbH Siemensstraße 25A 61352 Bad Homburg Germany Phone: +49 (0) 6172 17 17 771 envsales-gmbh@licor.com...
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Inc. LI-COR is a registered trademark of LI-COR, Inc. in the United States and other countries. Windows® is a trademark of Microsoft, Inc. macOS® is a trademark of Apple, Inc., registered in the US and other countries. All other trademarks are property of their respective owners.
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Notes on Safety This LI-COR product has been designed to be safe when operated in the manner described in this manual. The safety of this product cannot be assured if the product is used in any other way than is specified in this manual. The product is intended to be used by qualified personnel.
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Waste Electronic and Electrical Equipment (WEEE) Notice This symbol indicates that the product is to be collected separately from unsorted municipal waste. The fol- lowing applies to users in European countries: This product is designated for separate collection at an appropriate collection point.
Powering the analyzer and making measurements Identifying the LI-870 serial number Storing the LI-870 Section 3. Troubleshooting Smart Chamber or LI-8250 software not recognizing LI-870 Unable to Zero or Span the Instrument Instrument Reports -50 ppm CO2 or Measurements Jump Around Section 4. Maintenance...
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General CO2 Measurements H2O Measurements Appendix B. Equations summary Appendix C. Warranty...
LI-870. Refer to the Smart Chamber and LI- 8250 manuals for additional information. What's what If you have just taken delivery of your LI-870, check your packing list to ensure the following items have been included. LI-870 CO...
Smart Chamber or LI-8250 Multiplexer for storage and processing. LI-870 cable and tube assembly A 1.2 meter cable and tubing assembly is included with the LI-870 to connect the Part number: 9982-010. LI-870 with the Smart Chamber or LI-8250 Multiplexer. This assembly includes: Sealed USB-A to USB-B cable (part number 392-17654).
Section 1. Overview of the LI-870 Spares kit A spares kit is shipped with the LI-870 and contains the following. Part number: 9982-020. Description Quantity Part Number 1/4" Bev-A-Line® IV Plastic Tubing (12 meters) 8150-250 1/4" Quick-connect Straight Union 300-03123 Quick Connect Plug 0.165 with Hose Barb (Male)
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Section 1. Overview of the LI-870 Using the LI-870 CO₂/H₂O Analyzer...
Connecting the LI-870 to the Smart Chamber or LI-8250 Multiplexer is simple, only requiring a few steps. First, attach each end of the cable assembly to the LI-870. The USB-B end of the USB-A to USB-B cable is attached to the LI-870, while the USB-A end is attached to the Smart Chamber or LI-8250.
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Warning: The power output is 10-17 VDC with a center positive pin The output has a 2 amp maximum and is designed to only power the LI-870 CO Analyzer Accessory. Only use the power cable supplied with the LI-870 cable assembly (P/N 9982-010), and do not attempt to power any other devices with the Smart Cham- ber or LI-8250.
In the page of the Smart Chamber or LI-8250 interface, you will need to Settings connect to your LI-870 using the serial number. The label is on the bottom of the case. Warm up time The LI-870 will boot up as soon as power is supplied from the chamber. The optical bench should be allowed to warm up prior to taking measurements.
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Section 2. Using the LI-870 In the Smart Chamber and LI-8250 interface, you can see when your LI-870 optical bench has stabilized when the dot in the upper-left portion of any screen by the time stamp is green. If the bench is not stabilized, this dot will be red.
Note: For more information on post-purge, consult the Smart Chamber manual or find resources online at licor.com/env/support. The LI-870 should be stored in non-condensing conditions. If the instrument is stored in high humidity or moderate humidity for a long time while powered off, some optical components may temporarily become saturated with humidity.
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Section 2. Using the LI-870 Using the LI-870 CO₂/H₂O Analyzer...
870 and how to resolve them. If you can't find a solution here, if you need further assistance performing maintenance, or if you have other questions, contact your local distributor or LI-COR technical support for more help. Smart Chamber or LI-8250 software not recognizing LI-870...
Section 3. Troubleshooting Note: Do not open the LI-870 enclosure in the field. This can cause the tem- perature and pressure of the optics to become destabilized. More importantly, this can allow dust and debris into your analyzer. If possible, you should confirm whether your analyzer is working properly and troubleshoot any issues before tak- ing it out to the field.
Maintenance Cleaning the optical bench The LI-870 optical bench can be removed and cleaned with just a few steps if neces- sary. Generally speaking, you shouldn't undertake this procedure unless you've ruled out other potential problems. While the process itself is not difficult, you will have to set the instrument zero and span after reassembling the optical bench.
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The insulated optical bench will now be visible. Gently lift the optical bench out of the insulating foam and remove the cable connectors from the source and detector circuit boards. Gently grasp the plugs and pull them free. Using the LI-870 CO₂/H₂O Analyzer...
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Section 4. Maintenance Remove the screws that secure the source and detector (4 each), then separate the source and detector housings (with circuit boards attached) from the optical path. Clean the optical bench, source, and detector. Retrieve an optical path swab from the accessories kit. Dip one end into a 50:50 ethanol:water mixture (mild dish washing soap and water will work too) and carefully swab both ends of the optical path.
Perform a zero and span calibration (see User calibration on the facing page for instructions). Connecting to LI-870 for calibration Though the primary interface for the LI-870 is through the Smart Chamber or LI- 8250 software, you may also connect your LI-870 to the LI-COR LI-830/850 soft- ware to view data and for user calibration.
The software offers a variety of other features you may choose to explore. A more thorough explanation of the software is available at the LI-COR support site. However, for LI-870 soil applications, you will likely only the use the software for instrument calibration.
If using a scrubbing chemical, use a pump to draw air through the analyzer. Install a 10 to 20 cm length of tubing to the air outlet. This vent prevents ambient air from diffusing upstream into the optical cell. Using the LI-870 CO₂/H₂O Analyzer...
Section 4. Maintenance Flow Meter eter liters/min Zero Regulator Vent Vent When the CO concentration has stabilized, click the button. Zero CO Setting the primary CO span When choosing a span gas, we recommend a gas concentration that is close to - but still slightly above - the upper limit of what you expect to measure.
The information you need is provided on the cal- ibration sheet (included with the instrument or available for download from www.licor.com/env/support/). Under , enter the Settings > Calibrations > Advanced factory zero and span values for your instrument. Using the LI-870 CO₂/H₂O Analyzer...
After warmup (with pump): 0.42 A @ 12 VDC (5.0 W) average Power source: 8200-01S Smart Chamber or LI-8250 Multiplexer Measurements Measurement range: 0 to 20,000 ppm Accuracy: Within 1.5% of reading O Measurements Measurement range: 0 to 60 mmol mol Accuracy: Within 1.5% of reading Using the LI-870 CO₂/H₂O Analyzer...
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Appendix A. Specifications Using the LI-870 CO₂/H₂O Analyzer...
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S( α ) is the span function, and raw absorptance α is computed from where V and V are the raw detector sample and reference readings, and Z is the zeroing parameter. Span is a linear function of absorptance. Using the LI-870 CO₂/H₂O Analyzer...
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O. This is measured at the factory and accounted for in the computation of absorptance (equation B-10). There is also a band broadening effect that is accoun- ted for in the computation of concentration (equation B-14). absorptance α c is computed from B-10 Using the LI-870 CO₂/H₂O Analyzer...
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Appendix B. Equations summary where V and V are the raw detector signals for sample and reference, Z is the zero parameter, and X is a cross sensitivity parameter for the effect of water vapor on CO . Its value is reported on the calibration sheet as The empirical pressure correction function g () depends on CO absorptance and...
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α ' ) and CO concentration is shown in Figure B-1 on the facing page. (‘Typical’ because the exact relationship depends on the rela- tionship between absorptance and CO , which is the calibration curve.) Using the LI-870 CO₂/H₂O Analyzer...
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600 ppm. Calibration Equations The following equations describe the implementation of zero and span calibrations. Zeroing H When the command for zeroing water is received, the LI-870 computes the water zero from equation B-20, where are averaged for 5 seconds. B-20...
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S and S . First, it measures a new and computes a new from equation B-24. Then, it uses these plus the retained values ( from the previous normal span) to compute Using the LI-870 CO₂/H₂O Analyzer...
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Appendix B. Equations summary B-26 Given the new span slope S , it updates the span offset S by equation B-23. Spanning CO When the command for setting the CO span is received, along with the target con- centration C , the instrument computes S from equation B-28, where are averaged for 5 seconds.
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B-29. Then it uses these, plus the retained values ( α and β from the previous normal span) to compute B-34 Given the new span slope S , it updates the span offset S by equation B-28. Using the LI-870 CO₂/H₂O Analyzer...
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Inc.'s examination discloses to have been defective in material or workmanship without charge and only under the following conditions, which are: The defects are called to the attention of LI-COR, Inc. in Lincoln, Nebraska, in writing within one year after the shipping date of the instrument.
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The foregoing constitutes LI-COR, Inc.'s sole obligation and liability with respect to damages resulting from the use or performance of the instrument and in no event shall LI-COR, Inc. or its representatives be liable for damages beyond the price paid for the instrument, or for direct, incidental or con- sequential damages.
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Regional Offices LI-COR Biosciences GmbH Siemensstraße 25A 61352 Bad Homburg Germany Phone: +49 (0) 6172 17 17 771 envsales-gmbh@licor.com LI-COR Biosciences UK Ltd. St. John’s Innovation Centre Cowley Road Cambridge CB4 0WS United Kingdom Phone: +44 (0) 1223 422102 envsales-UK@licor.com LI-COR Distributor Network: www.licor.com/env/distributors...
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