manufacturer :       Dionex

model :                   AD 20

annotation :           Dokumente engl.

The AD20 Absorbance Detector is a dual-beam, variable wavelength photometer. Full spectral capability is provided by two light sources: a deuterium lamp for ultraviolet detection and a tungsten lamp for visible wavelength operation. The AD20 features programmable wavelength selection and automatic calibration for precision, reproducibility, and ease-of-use. The AD20 is designed for use with a variety of standard bore and microbore flow cells.

The AD20 can be controlled locally from the front panel, or from a remote holt computer via the optional Dionex DX LAN interface and PeakNet Software.

The AD20 Absorbance Detector consists of two single-unit DX 500 enclosures. The upper unit houses the detector electronics, while the lower unit houses the optical chassis.

The AD20 is designed to be stacked an top of other DX 500 modules. Figure B-1 in Appendix B illustrates the recommended stacking configuration for DX 500 systems.

Specifications

Electrical

Main Power            90 to 265 Vac, 47/63 Hz; 150 W Max, 100 W typical.

                              The Power supply is auto-sensing and requires no voltalte adjustment.

Fuse                       Two 3.15 amp fast-blow 1EC127 fuses (P/N 954745)

Analog Output        User-selectable full-scale output of 10, 100, or 1000 mV

Environmental

Operating               10 °C to 40 °C (50 'FF to 104 °F)

Temperature

Operating               5 to 95% relative humidity (non-condensing)

Humidity

Physical

Dimensions            22.5 cm W x 33.5 cm H x 42.0 cm D

                              (8.8 in W x 13.1 in H x 16.4 in D)

                              6 cm (2.4 in) clearance required behind the detector

Weight                    13.6 kg (30 Ibs)

Display and Keypad

Display                   Liquid crystal display with adjustable backlighting

Keypad                   26 buttons for entering commands and numerical values for screen parameters

Detector

Optical System      Dual-beam, fiber-optic beamsplitter and concave holographic diffraction grating

Light Sources         Deuterium lamp (30 W) for ultraviolet spectrum analysis;

                              tungsten lamp (10 W) for visible spectrum analysis

Wavelength            190 to 800 nm variable; continuous in 1 nm steps

Range

Wavelength           ± 1 nm

Accuracy

Bandwidth             8 nm

Absorbance            Discrete settings of 0.001, 0.002, 0.005, 0.01, 0.02, 0.05, 0.1,

Range                    0.2, 0.5, 1.0, and 2.0 AU

Autozero                2 AU

Capability

Autozero                ± 100 µAU

Accuracy

Noise                      < 10 µAU peak-to-peak at 254 nm, 2-second rise time,

                              flowing deionized water

Drift                        < 100 µAU/hour (after warm-up)

                              < 100 µAU/°C (after warm-up)

Filter Rise               Discrete settings of 0.05, 0.1, 0.2, 0.5, 1.0, 2.0, 5.0, or 10.0

Time                       seconds

Analog Output        Discrete settings of 0.001, 0.002, 0.005, 0.01, 0.02, 0.05, 0.1,

Range                    0.2, 0.5, 1.0, and 2.0 AUFS

Local                      Front panel controls and display status of all functions

Operation

Remote                 Four of the seven AD20 functions can be controlled via TTL
Operation               or Relay contacts

DX LAN                 All functions controlled by PeakNet Software an a PC, when

Operation               connected to the AD20 via the Dionex DX LAN interface
(Optional)

Flow Cell

Cell Body PEEK

Volume and            Standard bore cell, used with 4 mm (0.016 in) columns: 9

Optical Path           volume, 10 mm (0.002 in) optical path length

Length

Narrow bore cell, used with 4 mm (0.016 in) and 2 mm (0.008 in) columns: 7.5 µL volume, 6 mm (0.002 in) optical path length

                              Microbore cell, used with 2 mm (0.008 in) columns:

                              volume , 3 mm (0.01 in) optical path length

Maximum               1.38 mPa (200 psi) with a heat exchanger; 3.45 mPa (500 psi)

Operating               without a heat exchanger

Pressure

Chemical                The use of a base stronger than 0.1 M is not recommended, as

Compatibility          it will eich the silica windows.

Heat Exchanger

Coil for 2 mm         Volume of 20 µL; dispersion of 2.2 µL, at 1.0 mL/min

Columns

Coil for 4 mm         Volume of 60 µL; dispersion of 5.3 µL at 1.0 mL/min

Columns