RI-201H Refractive Index Detector

The Shodex RI-201H Refractive Index Detector incorporates a double temperature control system that ensures rapid start-up and exceptionally stable baseline performance, even under varying ambient conditions. A built-in solvent leak sensor provides an immediate output signal to halt pump flow in the event of an internal eluent leak, enhancing operational safety. The detector is designed for seamless integration with modern HPLC systems, featuring well-organized output signal terminals (recorder, integrator) and a USB communication port for high-level automation and data handling. Its deflection-type optical design, combined with a purge valve for easy flow switching, delivers reliable and reproducible measurements for a wide range of non-UV-absorbing compounds.

Operation-Manual-for-Shodex-RI-201H-Detector.pdf

Specifications

Parameter	Specification / Range
Detection Principle	Deflection type
Recorder Output	10 mV/FS; Range: 0.25 – 512 μRIU/10mV (12 steps)
Integrator Output	2 mV/μRIU (512 μRIU/V) or 8 mV/μRIU (128 μRIU/V)
Integrator Range (settable)	64 or 256 μRIU/1V
Time Constant	0.1, 0.25, 0.5, 1, 1.5, 2, 3, 6 sec (8 steps)
Temperature Control	30 – 50 °C (1 °C increment) or OFF
Baseline Shift Adjustment	0 – 200 (50 nRIU increments) at 10 mV output
Polarity	Positive / Negative selectable
Leak Sensor	ON / OFF selectable
Communication	USB port
Contact Signal Outputs	ERROR OUT, LEAK OUT, READY OUT (contact closure)
Flow Line Connections	IN: 1.6 mm O.D. × 0.25 mm I.D. SS tube; OUT: 2.5 mm O.D. × 1.5 mm I.D. PTFE tube
Power Requirements	100/120 VAC or 220/240 VAC (model dependent); 50/60 Hz
Fuse	Time-lag type, T3.15A / 250V
Dimensions (approx.)	Not specified in manual – contact Shodex
Weight (approx.)	Not specified in manual – contact Shodex

Performance

The Shodex RI-201H Refractive Index Detector provides continuous, real-time measurement of the refractive index difference between a sample cell and a reference cell, enabling universal detection of non-chromophoric compounds such as carbohydrates, polymers, alcohols, and organic acids. Its deflection-type optical system delivers high sensitivity and linear response over a wide dynamic range, while the dual-zone temperature control guarantees minimal baseline drift and short warm-up time. The detector is fully compatible with both analog data systems (recorder/integrator) and digital platforms via USB, supporting automated methods, remote monitoring, and event synchronization. With integrated leak detection and robust fluidics, the RI-201H is ideally suited for gel permeation chromatography (GPC), quality control, and routine analysis in pharmaceutical, chemical, and food industries.