Photodiode-Array Detector

S 4345/ S 4350 PDA Detector

S 4345 PDA Detector
S 4350 PDA Detector

The S 4345/ S 4350 photodiode-array (PDA) detector is for routine analysis and sophisticated research. The dual lamp design offers a wavelength range of 190 – 720 nm (256 Diodes) or 190 – 1015 nm (1024 diodes) with a low baseline noise. The front-accessible flowcell can be easily exchanged as well as the lamps which are accessible through a side panel in the instrument housing.


  • 4-Channel UV Detector
  • Integrated Peak Detector
  • Optional – Analog Output

4-Channel UV Detector

The S 4345/ S 4350 PDA Detector features 4-Wavelength channels to measure chromatograms at 4 different wavelengths at the same time. With this feature the optimum wavelength can be selected for each analyzed substance.

Integrated Peak Detector

The integrated Peak Detector works as a basic fraction collector. The peak detection level can be freely programmed for peak start and peak end to enhance the collection purity. An integrated 24V output for switching a solenoid valve is used for the fraction collection, which is automatically operated with a selectable time delay.

Optional – Analog Output

The S 4345/ S 4350 PDA Detector is available with an optional 4-Channel analog output. This D/A converter output option is offered to keep the system flexible to be used with any data acquisition software available.

Technical Specifications:

Wetted MaterialsStainless Steel / PEEK*, Teflon, Glass
Baseline Noise± 1 x 10-5 AU (@240 nm, 1 sec. Risetime)
Baseline Drift< 3 x 10-4 AU/h
Number of Diodes256 or 1024
Wavelength Range190 – 720 nm (256 Diodes)
190 – 1015 nm (1024 Diodes)
Wavelength Accuracy0.5 nm (256 Diodes)
0.3 nm (1024 Diodes)
Mean Pixel Pitch2.2 nm (256 Diodes)
0.8 nm (1024 Diodes)
Resolution (λ FWHM)7 nm (256 Diodes)
3 nm (1024 Diodes)
Linearity> 2.0 AU
Light SourceDeuterium Lamp, Tungsten Lamp
Wavelength ProgramProgrammable, 10 steps
Analog Output1x 1V (optional: 4x 1V)
Data Rate1 Hz – 100 Hz
Control FeaturesInternal Peak Detector with +24 V solenoid switching output
Dimensions (W x H x D)310 x 165 x 478 mm (S 4345)
396 x 165 x 478 mm (S 4350)
Power Supply100 – 250 ~V (47 – 63 Hz)
* depending on configuration