Refractometer & Viscometer


The BI-RIVS is a combination RI and Viscometry detector used in SEC/GPC determinations of the MWD using universal calibration.

A true Dual-Detector, refractometer, and viscometer, the only one of its kind available. The refractometer is an integral component of the viscometer bridge, measurement of concentration AND viscosity take place on the exact same sample segment, at the very same time. Compared to the more common “external” connection of the two detectors, the BI-RIVS Dual-Detector provides a factor of 2 to 5 higher sensitivity, near ZERO delay volume, and unsurpassed overall performance.

There is no need to wait for the sample “breakthrough” (the negative signal you can expect after each injection) or to adapt an “internal delay” to the number of columns you use like other viscometer designs require. The Dual-Detector will match any application you might think of, with any solvent, at any temperature up to 80°C.


Features at a Glance:
  • Dual Detector
  • Zero Dead Volume
  • Highest Sensitivity
  • Up to 80 °C



Use of a viscometer within a GPC/SEC system requires a source of a concentration signal to complete the necessary calculations. The difficulty is that the DRI Detector, which is usually utilized for this task, must deliver a corresponding concentration signal for each point on the viscosity curve. This is possible with two separate instruments, however precision of the results will be limited due to the volume difference of the detectors. A combo instrument, where both detectors are integral part of each other, overcomes these limitations and allows a much better determination of the sample under investigation.


Viscometer Specifications

Differential Pressure Range±5.0 kPa
Differential Pressure Gains1, 2, 4, 8
Inlet Pressure Range0 to 150 kPa
Sample Cell Volume15 µl
Shear Rate (1.0 ml/min)≤ 2,700 sec-1
Noise Level0.2 Pa, diff. Pressure Channel, 25 °C
Analog Output (integrator)1.0 Volt / 5 kPa FSD Differential Pressure
1.0 Volt / 100 kPa FSD Inlet Pressure

Refractive Index Detector Specifications

Refractive Index Range1.00 to 1.75
Cell Volume8 µl
Measurement Ranges (Δ Full Scale)6×10-4, 3×10-4, 1.5×10-4, 7.5×10-5
Noise Level< 2.5×10-9 ΔRIU, 25 °C
Analog Output (integrator)1.0 Volt FSD

Common Specifications

Total Detector Volume≈ 40 ml (including reservoirs)
Temperature Accuracy± 0.5 °C
Temperature Stability> 0.01 °C
Digital InterfaceRS-232C
Data Transfer Rate (baud)4800, 9600, 19200, 57600, 115200
Digital InputsFlush, Zero, Sync, Error
Digital OutputsSync, Error

Download Brochure

Available Downloads 

BI-RIVS Brochure PDF

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