RFM900-T refractometer

Measurement Features:

Software Features:



Conforms to GLP, OIML; ASTM D 5006, 1747, 2140, 1218; USP/EP/BP; and operational requirements of FDA regulation 21 CFR Part 11.

RFM900-T Refractometers

The RFM900-T Series of high precision Peltier temperature controlled benchtop refractometers, featuring a wide measuring range up to 1.70 RI and new 7” touchscreen user interface, are ideally suited for use in applications within the chemical, petrochemical, pharmaceutical, flavours and fragrance industries as well as in academic research.

Building upon our legacy

Bellingham + Stanley has been manufacturing refractometers for over a century and the latest refractometers build on that legacy. The instrument’s new case is ergonomically designed so that any spills are dealt with by the sloping shape of the case or by the PEEK spill barrier that surrounds the shallow, easy-clean stainless steel prism dish. The prism dish is shaped to hold sufficient sample for measurement whilst regaining a large enough surface area for rapid temperature stabilisation to occur. A Kalrez® gasket has been chosen as the prism seal due to its almost impermeable nature to most chemicals. The sample cover forms a seal to prevent evaporation, particularly important when working with volatile solutions such as aromatic oils, and is interchangeable so that a presser type can be fitted for more viscous samples.

New larger, quieter fan

A single large fan helps to regulate temperature as part of the Peltier control system. Operating at low speeds creates less noise whilst still offering the same excellent temperature control you’d expect to find in a Bellingham + Stanley refractometer. Positioned at the base of the unit, the RFM900-T’s fan is designed to be protected from harsh environments, whilst still being easily accessible for maintenance.

Touchscreen display & RFID technology

RFM900-T Refractometer touchscreen

Inherent to the new design is the new high definition, capacitive touchscreen display that not only facilitates operation in factory environments, even when operated whilst wearing gloves, but also serves as the centrepiece for the new software. Combined, the touchscreen and GUI help the operator quickly manoeuvre through the user and configuration menus. On-screen graphical prompts support simple operation such as method loading, calibration and routine maintenance.

RFID swipe technology comes as standard, providing clearance and a log of operator and configuration functions – especially useful when being used in FDA-regulated environments operating in accordance with 21 CFR Part 11, or where good practice is adopted, e.g. as part of HACCP.  

Methods and measuring

Measurements with the RFM900-T are made through a familiar measuring mode or by way of a simple Methods system with one-touch configuration of scale, temperature and data storage, with up to 4000 results being saved alongside pre-set limits that can be used as an audit tool. Methods may be user-defined or selected from the on-board library, such as the PHR-MEAN method that allows a number of individual readings from a single batch of pharmaceutical product to be measured with the resultant mean being displayed and recorded in accordance.

Methods for petrochemical applications include ASTM D 1218, D 1747 and D 5006. Additionally, a method is included for ASTM D 2140 that requests external data input of viscosity, density and relative density so that calculation of carbon-type composition of electrical insulating oil used to cool high-power transformers may easily be calculated without the need to visually interpret difficult correlation charts.

RFM900-T Series refractometers are supplied with free software for your PC so that when connected to a network via Ethernet connection, the instrument can be remotely handed by an external service or support centre for diagnostics or even be used for training or installation qualification.

USB ports are standard and facilitate connections to peripherals including an external keyboards, barcode readers or memory sticks. Memory sticks can be used to transfer secure files or as part of a “Back-up & Clone” process that allows rapid configuration interchange across a number of instruments at a customer site or for setting up hire equipment on loan for a short period of time.

Measurement Specifications
RFM960-T RFM970-T
Refractive Index
Sugar (°Brix)

1.30 – 1.70

1.30 – 1.70
Refractive Index
Sugar (°Brix)


0.000001 (selectable up to 6 d.p.)
Refractive Index
Sugar (°Brix)


Refractive Index
Sugar (°Brix)

± 0.00005
± 0.05

± 0.000005 (6 d.p.)
± 0.005
User Scale Library 20+ pre-programmed scales including HFCS (3), sugar (4), sucrose SG (3), ASTM D 2140, PHR-MEAN, Urea and more; plus customer programmable user scales via PC.
Reading Time Minimum 4 seconds (dependant on precision required)
Measuring Temperature Range 0°C or 10°C below ambient whichever is greater to 80°C
Temperature Sensor Accuracy ± 0.03°C
Sample Temperature Stability ± 0.02°C
Temperature Compensation
Sucrose (°Brix)
AG Fluid
User Defined

5 – 80 °C
5 – 40 °C
Simple coefficient (units/°C) or polynomial function
Temperature Stability Checks None/delay time/repeatability/ Smart (independently selectable by Method)
Sample Illumination Light Emitting Diode 589nm (100,000+ hours)
Prism / Dish Artificial Sapphire / Stainless Steel 316 / PEEK (spill barrier)
Prism Seal Kalrez®
Interfaces 3 x USB (A), 1 x USB (B), 1 x Ethernet, 1 x Serial (RS232)
Power Instrument: 24 V DC, ±5%, <2A
External PSU: 100-240V, 50-60Hz (supplied)
Humidity Range <90% RH (non condensing)
Order Codes
19-60 RFM960-T Peltier temperature controlled refractometer with latest integral 7” full colour
touch-screen, high definition display and USB/LAN connectivity. Supplied with pack of two RFID tags, instruction manual and certificate of conformity.
19-70 RFM970-T Peltier temperature controlled refractometer with latest integral 7” full colour
touch-screen, high definition display and USB/LAN connectivity. Supplied with pack of two RFID tags, instruction manual and certificate of conformity.
22-498 Spare filters for RFM-T models (pack of 12)
22-467 Validation documentation (only) for RFM900-T IQ/OQ/PQ within pharmaceutical environments
55-14 Dot-matrix impact printer, 24 column: Serial (RS232), 230V (UK/Euro plug)
55-16 Dot-matrix impact printer, 24 column: Serial (RS232), 110V (USA plug)
54-02 Serial interface cable for printer
55-86 USB mini keyboard