Subscribe to Our Youtube Channel
Related Manuals for Waters ACQUITY UPC2
Summary of Contents for Waters ACQUITY UPC2
- Page 1 ACQUITY UPC Photodiode Array Detector Overview and Maintenance Guide Revision A Copyright © Waters Corporation 2012 All rights reserved...
-
Page 2: Copyright Notice
This document is believed to be complete and accurate at the time of publication. In no event shall Waters Corporation be liable for incidental or consequential damages in connection with, or arising from, its use. -
Page 3: Table Of Contents
About the detector control panel..................30 Using a cuvette ........................31 Shutting down the detector ....................34 Maintaining the detector ..................... 34 Contacting Waters technical service ................. 34 Maintenance considerations....................35 Proper operating procedures ..................... 36 Maintaining the leak sensor ....................37 Replacing the detector’s leak sensor................. - Page 4 Cleaning the instrument’s exterior..................53 Spectral contrast theory ...................... 54 Comparing absorbance spectra ..................54 Representing spectra as vectors ..................55 Spectral contrast angles ....................57 Undesirable effects ......................60 Error messages and troubleshooting .................. 64 Startup error messages ...................... 64 Error messages preventing operation................
-
Page 5: Overview
Overview The Waters ACQUITY UltraPerformance Convergence Chromatography (ACQUITY UPC ™) photodiode array (PDA) detector is an ultraviolet- and visible-wavelength (UV/Vis) spectrophotometer designed for use in the ACQUITY UPC system. Empower™ or MassLynx™ software can control the detector for LC/MS and LC applications. - Page 6 Optics assembly light path: Grating Order filter Window Photodiode array Slit (50-µm) M1 mirror Spectrograph mirror and mask TP02819 Lamp and Flow cell Filter Flag lamp optics The following table describes the optics assembly components. Optics assembly components: Component Function Filter flag Influences the light entering the flow cell.
- Page 7 Optics assembly components: (Continued) Component Function Flow cell Houses the segment of the flow path (containing eluent and sample) through which the polychromatic light beam passes. Grating Blazed, holographic diffraction grating that disperses light into bands of wavelengths and focuses them onto the plane of the photodiode array.
-
Page 8: Calculating Absorbance
Calculating absorbance The detector computes absorbance by subtracting the dark current (see “Dark current” on page 14) and reference spectrum from the acquired spectrum. Absorbance is based on the principles of Beer’s law. Beer’s law The relationship between the quantity of light of a particular wavelength arriving at the photodiode and the concentration of the sample passing through the flow cell is described by the Beer-Lambert law (commonly called Beer’s law). - Page 9 Absorbance as a function of concentration: Ideal Actual Working range Background absorbance Concentration Overview...
-
Page 10: Flow Cell Operating Principles
The Waters TaperSlit flow cell, so-called because of the shape of the flow cell exit face, matches the shape of the spectrograph slit. Compared with a conventional flow cell with a cylindrical shape, the detector achieves higher light throughput for a given spectral resolution with the TaperSlit cell design. - Page 11 The grating images the slit onto the photodiode array. The angle of diffraction from the grating determines the wavelength that strikes a particular photodiode in the array. The following figure shows an absorbance spectrum of benzene. Note that the wavelength resolution is sufficient to resolve five principal absorption peaks. Benzene spectrum at 1.2 nm resolution: Measuring light at the photodiode array The photodiode array detector measures the amount of light striking the...
- Page 12 Photodiodes discharged by light: Sample in flow cell Deuterium lamp absorbs at specific wavelengths. Grating Flow cell Light from grating dispersed onto diodes. Slit Mirror The detector measures the amount of current required to recharge each photodiode. The current is proportional to the amount of light transmitted through the flow cell over the interval specified by the diode exposure time.
- Page 13 You specify the exposure time in the General tab of the PDA Instrument Method Editor: Auto Exposure or Exposure Time. For details, refer to the Empower or MassLynx online Help. For best signal-to-noise performance, adjust the wavelength range to Tip: optimize autoexposure computations.
- Page 14 signal-to-noise ratio over the wavelength range of your analysis (see the next section, “Optimizing the signal-to-noise ratio”). Optimizing the signal-to-noise ratio To optimize signal-to-noise ratios, choose an acquisition wavelength range that includes only the wavelengths of interest. It is also important that the range be one in which the mobile phase absorbs only minimally.
- Page 15 Digital filter settings for data rates: (Continued) Data Slow Normal Fast Rate 0.800 0.400 0.200 0.400 0.200 0.100 0.200 0.100 0.050 0.100 0.050 0.025 0.050 0.025 0.0125 Lower filter-time constant settings produce these effects: • Narrow peaks, with minimal peak distortion and time delay •...
- Page 16 Filter-time constant comparison: 0 sec 1 sec 2 sec Time (minutes) Although the peak shape shows some distortion and the signal output is Tip: delayed with different filter-time constants, the peak area remains the same. Selecting the appropriate sampling rate A sufficient number of points must fall across a peak to define its shape.
- Page 17 If the Points Across Peak value for the narrowest peak of interest is less than 15, to improve peak integration reproducibility, specify a higher sampling rate in the instrument method. If the value is greater than 100, specify a lower sampling rate.
- Page 18 Computing absorbance The detector calculates absorbance values before transmitting the data to the Empower or MassLynx database. It does so as follows: • Computes the absorbance at each diode using the dark current and reference spectrum (see “Calculating absorbance” on page •...
- Page 19 Absorbance The detector calculates the absorbance for each diode at the end of each exposure time using the following equation: – Absorbance n ------------------------ - Rn Dn – where S = obtained during sample analysis D = obtained during the dark current test R = obtained from the reference spectrum n = diode number Resolution...
-
Page 20: Detector Capabilities
Detector capabilities The detectors, whose capabilities are described in the table below, operate at wavelengths ranging from 190 to 800 nm and can sample up to 80 data points per second. Detector capabilities: Capability Description Full, three-dimensional spectrum Enables collecting the full spectral range data throughout the chromatogram. -
Page 21: Preparing The Detector
• none of the shipping containers or unpacked items are damaged. If you discover any damage or discrepancy when you inspect the contents of the cartons, immediately contact the shipping agent and your local Waters representative. Preparing the detector... -
Page 22: Installing The Detector
Customers in the USA and Canada must report damage and discrepancies to Waters Technical Service (800 252-4752). Others must phone their local Waters subsidiary or Waters corporate headquarters in Milford, Massachusetts (USA), or visit the Waters Web site at www.waters.com. - Page 23 Proper placement for drip management system: Guides for feet placement Drain routing hole for drip management system Attach the solvent bottle tray so it is next to the convergence manager. Installing the detector...
- Page 24 ACQUITY UPC PDA detector in an ACQUITY UPC system: Detector Column manager Solvent bottle tray TP03453 Convergence manager Sample manager - fixed loop Binary solvent manager...
-
Page 25: Plumbing The Detector
Plumbing the detector To avoid chemical hazards, always observe Good Laboratory Warning: Practices when operating your system, handling solvents, or changing tubing. See the Material Safety Data Sheets for the solvents you use. Plumbing the detector involves connecting the flow cell. To avoid particulate contamination in the flow cell, flush any columns you are connecting to the detector before connecting them. - Page 26 Use the alignment pin on the optics bench as a guide to installing Tip: the flow cell. Dowel alignment pin TP03457 Gently push the front of the flow cell assembly until it seats on the front alignment pin. Continue to insert the flow cell until the three thumbscrews align with their holes in the optics bench.
- Page 27 Finger-tighten the thumbscrews, and then secure them with a 1/4-inch flat-blade screwdriver. Flow cell ID connector Lamp Thumbscrews Tubing outlet Tubing inlet TP03458 Plumbing the detector...
-
Page 28: Installing The Multi-Detector Drip Tray
Remove the protective cover from the PEEK cell inlet tubing, and connect the tubing to the flow cell inlet, confirming that the label on the tubing matches the type of detector and flow cell in your system. Flow cell tubing for the ACQUITY UPC PDA detector is provided Note: in two lengths:... -
Page 29: Making Ethernet Connections
Installing the multi-detector drip tray (bottom view): Screws Extended Plastic plastic feet rivets Return the ACQUITY UPC PDA detector to its original position atop the other detector. Making Ethernet connections To make Ethernet connections: Unpack and install the preconfigured workstation. Connect one end of one Ethernet cable to the network switch, and then connect the other end to the Ethernet card, on the workstation. -
Page 30: I/O Signal Connector
To avoid electrical shock, observe these precautions: Warning: • Use power cord SVT-type in the United States and HAR-type (or better) in Europe. For other countries, contact your local Waters distributor. • Power-off and unplug the detector before performing any maintenance on the instrument. -
Page 31: Starting The Detector
To connect to the electricity source: Use a line conditioner and uninterruptible power supply Recommendation: (UPS) for optimum long-term input voltage stability. Connect the female end of the power cord to the receptacle on the rear panel of the detector. Connect the male end of the power cord to a suitable wall outlet. - Page 32 If you must power-on the detector before the eluent is flowing, extinguish the lamp. You can do this in one of three ways: • In the Instrument Method Editor (in Empower; Inlet Editor in MassLynx), specify a Lamp Off event in the Events table. •...
-
Page 33: Monitoring Detector Leds
Information regarding the error that caused the failure can be found in the console. Constant red Indicates a detector failure that prevents further operation. Power-off the detector, and then power-on. If the LED is still steady red, contact your Waters service representative. Starting the detector... -
Page 34: About The Detector Control Panel
About the detector control panel When Empower software controls the system, the detector’s control panel appears at the bottom of the Sample Set Editor page. When MassLynx software controls the system, the detector’s control panel appears at the bottom of the Inlet Editor window. Detector control panel: Lamp On/Off LED Status... -
Page 35: Using A Cuvette
Modifiable detector control panel items: (Continued) Control panel item Description Shutter Displays the shutter position (Open, Closed, or Erbium). Lamp On/Off icon Ignites or extinguishes the detector lamp (turns lamp on or off). You can access additional functions by right-clicking anywhere in the detector control panel. - Page 36 Because the measurement is actually a composite of both the Restriction: contents of the cuvette and the flow cell, you need to perform cuvette measurements under identical flow cell conditions. If you store spectra and acquire new spectra for subtraction, you need to be aware of differences, if any, in flow cell conditions.
- Page 37 With the spring guide facing you, gently insert the cuvette (containing eluent) up and under the guide, with the cap facing upward (into the holder) and a frosted side of the cuvette facing up. Refer to the figure on page Recommendations: •...
-
Page 38: Shutting Down The Detector
Contacting Waters technical service If you are located in the USA or Canada, report malfunctions or other problems to Waters Technical Service (800 252-4752). If you are located elsewhere, phone the Waters corporate headquarters in Milford, Massachusetts (USA), or contact your local Waters subsidiary. Our Web site includes phone numbers and e-mail addresses for Waters locations worldwide. -
Page 39: Maintenance Considerations
Empower or MassLynx software version and serial number • Workstation model and operating system version For complete information on reporting shipping damages and submitting claims, see Waters Licenses, Warranties, and Support Services. Maintenance considerations Safety and handling Observe these warning and caution advisories when you perform maintenance on your detector. -
Page 40: Proper Operating Procedures
“Starting the detector” on page Spare parts Replace only parts mentioned in this document. For spare parts details, see the Waters Quality Parts Locator on the Waters Web site’s Services & Support page. Recommendations: • For optimal baseline stability, keep the detector door closed at all times. -
Page 41: Maintaining The Leak Sensor
Flushing the detector To avoid damaging the detector, do not exceed the Caution: 41369 kPa (413.69 bar, 6000 psi) pressure limitation of the flow cell. To flush the detector: Stop the solvent flow to vent the system: From the console, select Binary Solvent Manager in the system tree. To avoid burn injuries resulting from skin contact with Warning: pressurized, liquid CO... - Page 42 Resolving detector leak sensor errors After approximately 1.5 mL of liquid accumulates in the leak sensor reservoir, an alarm sounds, indicating that the leak sensor detected a leak. To avoid personal contamination with biologically Warning: hazardous or toxic materials, wear clean, chemical-resistant, powder-free gloves when handling the leak sensor and its reservoir.
- Page 43 To avoid damaging the leak sensor, do not grasp it by the Caution: ribbon cable. Remove the leak sensor from its reservoir by grasping it by its serrations and pulling upward on it. Serrations If you cannot easily manipulate the leak sensor after removing it Tip: from its reservoir, detach the leak sensor connector from the front of the instrument (see...
- Page 44 Roll up a nonabrasive, lint-free wipe, and use it to absorb the liquid from the leak sensor reservoir and its surrounding area. Rolled up lint-free wipe Leak sensor reservoir With a cotton swab, absorb any remaining liquid from the corners of the leak sensor reservoir and its surrounding area.
- Page 45 Align the leak sensor’s T-bar with the slot in the side of the leak sensor reservoir, and slide the leak sensor into place. TP02892 T-bar TP02908 Slot in leak sensor reservoir Leak sensor installed in reservoir If you detached the leak sensor connector from the front of the instrument, reattach it.
-
Page 46: Replacing The Detector's Leak Sensor
Replacing the detector’s leak sensor The leak sensor and its reservoir can be contaminated Warning: with biohazardous and/or toxic materials. Always wear clean, chemical-resistant, powder-free gloves when performing this procedure. Required materials • Clean, chemical-resistant, powder-free gloves • Leak sensor To replace the detector leak sensor: Open the detector door, gently pulling its right-hand edge toward you. - Page 47 Remove the leak sensor from its reservoir by grasping it by its serrations and pulling upward on it. Serrations Unpack the new leak sensor. Maintaining the detector...
-
Page 48: Maintaining The Flow Cell
Align the leak sensor’s T-bar with the slot in the side of the leak sensor reservoir, and slide the leak sensor into place. TP02892 T-bar TP02908 Slot in leak sensor reservoir Leak sensor installed in reservoir Plug the leak sensor connector into the front of the instrument. In the console, select your detector from the system tree. - Page 49 Conditions other than a dirty flow cell can cause decreased lamp Tip: intensity. For more information, refer to “Error messages and troubleshooting” on page Flow cell maintenance consists of • flushing the flow cell. • removing the flow cell. • installing the flow cell assembly.
- Page 50 52). If the lamp diagnostic test fails and the lamp has not been used more than 2000 hours or 1 year from date of purchase (whichever comes first), call Waters Technical Service (see page 64). Replacing the flow cell Before replacing the flow cell, you must power-off the detector, stop the solvent flow, and vent the system pressure.
- Page 51 Enter zero flow in the composition field or press the Stop Flow icon and enter a flow rate of zero. The system will vent to atmospheric pressure through the vent valve in the ACQUITY UPC Convergence Manager. Open the detector front panel door. Disconnect the detector’s inlet and outlet tubing and the flow cell identification cable from their appropriate connections.
- Page 52 Gently push the front of the assembly until it seats on the front alignment pin. Installing the flow cell assembly: Dowel alignment pin TP03457 10. Continue to insert the flow cell until the three thumbscrews align with their holes in the optics bench. To prevent the flow cell from binding and ensure that it is Caution: properly seated in the optics bench, alternate between tightening the...
-
Page 53: Replacing The Lamp
Replacing the lamp Waters warrants 2000 hours of lamp life for the lamp, or one year since date of purchase, whichever comes first The software senses the ACQUITY UPC PDA lamp when you install it, and records its serial number and installation date in the lamp change record table. - Page 54 Power-off the detector, and disconnect the power cable from the rear panel. To save time, leave the detector powered on for 15 minutes Alternative: after you power-off the lamp. Doing so will allow the fan to blow cool air on the lamp, cooling it faster. Be sure to power-off the detector, and disconnect the power cable from the rear panel after 15 minutes has elapsed.
- Page 55 Captive screws Lamp power connector To avoid laceration injuries, use care when disposing of Warning: the lamp. The lamp’s gas is under a slight negative pressure, so take care not to shatter the glass bulb. To avoid skin oils or dirt from adversely affecting the Caution: detector’s operation, do not touch the new lamp’s glass bulb.
-
Page 56: Reading Lamp Energy
Gently push the lamp forward until it bottoms into position. Ensure the lamp is flush against the optics bench. To prevent the lamp from binding and ensure that it is Caution: properly seated in the lamp housing, alternate between tightening the captive screws and pushing the lamp forward. -
Page 57: Cleaning The Instrument's Exterior
Suspect a faulty fuse when • the detector fails to power-on; • the cooling fan does not operate. Replace both fuses, even when only one is faulty. Requirement: To replace the fuses: Replace both fuses, even when only one is open or otherwise Requirement: defective. -
Page 58: Spectral Contrast Theory
Spectral contrast theory The spectral contrast algorithm compares the UV/Vis absorbance spectra of samples the detector collects. This chapter describes the theory on which the algorithm is based, explaining how it exploits differences in the shapes of the absorbance spectra. It also explains how spectral contrast represents those spectra as vectors, determining whether differences among them arise from the presence of multiple compounds in the same peaks (coelution) or from nonideal conditions such as noise, photometric error, or solvent effects. -
Page 59: Representing Spectra As Vectors
Comparing spectra of two compounds: Compound A: -------------- - Compound B: -------------- - 0.40 245 nm 257 nm Compound A 0.20 Compound B 0.00 220.00 240.00 260.00 280.00 300.00 320.00 340.00 344.5063 nm, 0.4595 AU Representing spectra as vectors The spectral contrast algorithm uses vectors to quantify differences in the shapes of spectra, converting baseline-corrected spectra to vectors and then comparing the vectors. - Page 60 To prevent detector noise, don’t include wavelengths where there is little Tip: or no analyte absorption. Vectors derived from two wavelengths The spectral contrast algorithm uses vectors to characterize spectra. To understand the vector principle, consider the two vectors in the figure below, which are based on the spectra depicted in the previous figure.
-
Page 61: Spectral Contrast Angles
Vectors derived from multiple wavelengths When absorbance ratios are limited to two wavelengths, the chance that two different spectra share the same absorbance ratio is greater than if comparison is made using absorbance ratios at many wavelengths. Therefore, the spectral contrast algorithm uses absorbances from multiple wavelengths to form a vector in an n-dimensional vector space, where n is the number of wavelengths from the spectrum. - Page 62 Spectra that produce a large spectral contrast angle: Spectral contrast angle: 62.3° Compound A Compound B Wavelength (nm) Spectra with similar shapes In the following figure, the absorbance spectra of two compounds, A and B, are similar. They therefore produce a small spectral contrast angle (3.0°).
- Page 63 Spectra with a small spectral contrast angle: Spectral contrast angle: 3.0° Compound A Compound B Wavelength (nm) Differences between spectra of the same compound Small but significant differences between absorbance spectra can occur because of factors other than those due to the absorbance properties of different compounds.
-
Page 64: Undesirable Effects
Absorbance spectra of a compound at two concentrations: Normalized spectra of a compound at different concentrations Spectral contrast angle: 3.4° Region of little or no analyte absorption Wavelength (nm) Undesirable effects Shape differences between absorbance spectra can be caused by one or more of the following undesirable effects: •... - Page 65 Detector noise Statistical and thermal variations add electronic noise to the detector’s absorbance measurements. The noise, which manifests itself as fluctuations in the baseline, is known as baseline noise. The magnitude of any absorbance differences caused by statistical and thermal variations can be predicted from the instrument noise in the baseline region of a chromatogram.
- Page 66 Threshold angle In addition to computing spectral contrast angles, the spectral contrast algorithm also computes a threshold angle. The threshold angle is the maximum spectral contrast angle between spectra that can be attributed to nonideal phenomena. Comparison of a spectral contrast angle to its threshold angle can help determine whether the shape difference between spectra is genuine.
- Page 67 Effects of solvent concentration on the absorbance spectrum of p-aminobenzoic acid: Effect of concentration Note that position of maxima can be shifted. Wavelength (nm) Spectral contrast theory...
-
Page 68: Error Messages And Troubleshooting
Messages requiring you to perform corrective action including messages encountered at startup and during operation. • Messages requiring you to cycle power, and then contact Waters Technical Service personnel if an error persists (see “Contacting Waters technical service” on page 34). - Page 69 Electronic 1. Cycle power to the failed communication with detector. the digital signal 2. If problem persists, processor failed. contact Waters Technical Service to replace the personality card. Command received Data system 1. Close the data system while initializing. (Empower or and wait until both front Unable to process.
- Page 70 Energy level low. 1. Clear the flow cell and establish flow. 2. If step 1 does not work, replace the lamp. 3. If problem persists, contact Waters Technical Service. Lamp hours counter Lamp hour usage Replace lamp. exceeded threshold exceeded.
-
Page 71: Error Messages Preventing Operation
When you encounter such an error, ensure that • the flow cell is clean; • the front door is shut securely. Cycle power to the detector. If the terminating error persists, contact Waters Technical Service. Instrument error messages: Error Message Description... - Page 72 Leak detected Leak in detector Follow the procedure to resolve a detector leak sensor error on page Leak Detector not Leak detector is not 1. Connect the leak present present or is not detector. connected. 2. Contact Waters Technical Service.
- Page 73 Shutter failed to home Shutter could not home. 1. Flush the flow cell. 2. Establish flow. 3. Reset communications from the control panel or console. 4. Contact Waters Technical Service Temperature controller Personality card Contact Waters A/D failed electronic error.
-
Page 74: Detector Troubleshooting
Detector troubleshooting Detector troubleshooting: Symptom Possible cause Corrective action Both LEDs unlit No power 1. Inspect line cord connections. 2. Test electrical outlet for power. Open (spent) or Replace fuse (see defective fuse page 52). Change in reference Air bubbles trapped in •... - Page 75 Detector troubleshooting: (Continued) Symptom Possible cause Corrective action Detector not Bad or disconnected Inspect cable responding to console cable connections, tighten connectors, or replace cable. Configuration problem Check Ethernet configuration. For details, see Empower or MassLynx online Help. Leak detected Leak in detector Follow the procedure to resolve a detector leak...
-
Page 76: Specifications
Specifications This section lists specifications for the ACQUITY UPC PDA Detector. ACQUITY UPC PDA detector specifications Physical specifications: Attribute Specification Height 19.3 cm (7.6 inches) Depth 60.7 cm (23.9 inches) Width 34.3 cm (13.5 inches) Weight 15.9 kg (35.0 pounds) Environmental specifications: Attribute Specification... - Page 77 Electrical specifications: (Continued) Attribute Specification Grounded AC Line voltages, nominal Voltage range 100 to 240 VAC nominal Frequency 47 to 63 Hz Fuse 3.15 A at 250 V Power consumption 185 VA nominal a. Protection Class I – The insulating scheme used in the instrument to protect from electrical shock.
-
Page 78: Solvent Considerations
Performance specifications: (Continued) Item Specification Noise (wet) <10 μAU (254 nm, 2 Hz, 1 sec TC, 3.6 BW res, 10 mm analytical flow cell, flow rate 0.5 mL/min, 90:10 H2O:ACN If you will be using the PDA detector in Important: an ACQUITY UPC system (using CO ) where... -
Page 79: Solvent Miscibility
Solvent miscibility Liquid carbon dioxide functions as a nonpolar organic solvent much like iso-octane or n-hexane. At conditions slightly above the critical point, liquid carbon dioxide would possess a miscibility number of 28 or 29. As temperature and pressure are increased on liquid carbon dioxide, its solvating power and miscibility increase. - Page 80 UV cutoff wavelengths for common chromatographic solvents: (Continued) UV cutoff UV cutoff Solvent Solvent (nm) (nm) Ethanol Petroleum ether Ethyl acetate Pyridine Ethyl ether Tetrahydrofuran Ethyl sulfide Toluene Ethylene dichloride Xylene For more solvent considerations and detailed solvent information, see the ACQUITY UPC System Guide.
- Page 81 Beer’s law overview photodiode array overview plumbing connections power LED electricity source reference spectrum Ethernet, making signal connector contacting Waters Technical Service specifications control panel, detector operational cuvette starting holder, illustrated – troubleshooting removing diagnostic tests...
- Page 82 errors lamp energy, reading fatal leak sensor startup maintaining Ethernet connections, making replacing exposure time parameter lamp monitoring filters power noise second-order flow cell maintaining, flow cell comparison maintenance conditions considerations flushing leak sensor installing safety considerations maintaining match angle, photometric error effects removing maximum absorbance replacing...
- Page 83 Waters Technical Service, contacting solvent angle, photometric error effects wavelength solvent changes derived vectors spare parts specifications electrical environmental physical...
- Page 84 Index-4...
Need help?
Do you have a question about the ACQUITY UPC2 and is the answer not in the manual?
Questions and answers