Robust
Manufacture:
Construction materials have been carefully selected
to withstand common samples and solvents. The chemical resistant Polyurethane
Foam case offers a seal against moisture and corrosion, whilst materials
in contact with the artificial sapphire prism are of the highest specification
including Kalrez® gaskets and PEEK spill barriers as standard.
Unlike many manufacturers that use external heatsinks, the qualifying refractometers’ temperature control system comprises internal elements to prevent samples from covering and therefore insulating heatsinks. Pulse controlled airflow through filtered ducting ensures there is no contamination to the optics, electronics or heatsinks.
Optional Harsh Environment Protection includes special filter pods and vent exit covers that stop samples seeping into the aforementioned qualifying refractometers ducting. Optional keypad covers and waterproof power supplies (IP66) are also available for all models, ensuring performance year after year and in the worst of conditions!Installation
Wizard:
Qualifying refractometers are factory set to operate
in refractive index mode at 20ºC and in English language. After
purchase, the instrument runs an installation wizard on start up that
helps users configure the operation. Parameters include language, date/time,
scale, temperature, security and RFID tag allocation.
Measurement
Features:
Bellingham + Stanley refractometers offer one of the highest
measurement specifications available. Results may be displayed in refractive
index or Brix. Alternatively, over 15 industry standard scales may be
loaded from the instrument library without the need for expensive and
fragile ‘plug-in cards’. Customer defined scales may also
be created using software available free of charge from this site, so
creating special scales to display a particular chemical % concentration
is never a problem.
Sample containment is vital in providing a rapid temperature response. A carefully shaped “easy clean prism dish” ensures only the right amount of sample is applied to the sapphire prism, optimising temperature stabilisation time. Carefully placed temperature sensors ensure rapid response so that two internal Peltier devices quickly control the sample temperature. Even the airflow to the Peltiers is considered to ensure maximum performance. When in ‘SMART temperature stability mode’, the refractive index or other scaled result is only displayed when both reading and temperature has stabilised. ICUMSA temperature compensation is also provided with the option to load User Temperature Compensation to correct to any specified reference temperature.
Having a resolution to three decimal places, the
ADP440+ polarimeter competes with some of the best instruments on the
market today but at the fraction of the cost. Measurement readout can
be independently set by simple push button selection and for ease-of-use,
the instrument can be configured to read directly in Specific Rotation, % Concentration and Sugar
Purity amongst other user definable scales by way of a simple Methods
System.
Reading time is selectable between 4 and 30-seconds, allowing for high precision measurement. Temperature of the instrument chamber can be measured or the sensor can be placed in the centre arm of a standard glass or water-jacketed tube in order to show the actual sample measurement prior to any compensation being made. Low volume tubes for precious or rare samples can also be accommodated whilst optional slotted lids facilitate sample/water tube access and physical stability.
The Optical Density of the sample is also displayed allowing the user to gauge measurement reliability.
Purity:
The ADP440+ polarimeter may form the hub of a sugar purity system. Brix
is input by either combining a suitable refractometer directly to the instrument
or via the instrument keyboard. Results may then be displayed or output
in accordance with recognised calculations.
Sample
Cover ‘Read’ Function:
Qualifying refractometers feature a lightweight, non-contact sample
cover that prevents ambient light entering the optics. The instrument
may also be programmed so that replacement of the cover instigates a reading,
negating the need to press the read button.
User
Interfaces:
Qualifying instruments have a back lit ‘blue light’ LCD
dot matrix screen that can be inverted to show two display styles,
with legend available in a choice of at least four different languages¹.
A powerful microprocessor lays behind the simple ‘telephone style’ keypad providing standard measurement or industry specific METHODS. The reading display can be configured to show one or a number of different measurement parameters along with instrument configuration, batch code and operator identifiers in accordance with GLP and the technical requirements of FDA regulation 21 CFR Part 11.
Navigation is by cursor or numeric index with access protected to three levels (low/medium/high) depending on the security of measurement required. Users may be specifically defined, controlling access to specific levels or the entire instrument menu. After a specified period of instrument inactivity, the software will ‘time-out,’ requiring further user identification. Authorised use of the instrument is therefore protected by keypad PIN entry or by way of RFID tag on the RFM900 and ADP440+.
In low or medium security levels, qualifying instruments can store up to 700 results that can be displayed in tabular form on the instrument display. Results may even be sorted by user or date as required. Alternatively the stored data, along and a configuration file that logs all changes made to the instrument set-up, may be extracted to PC by special Data Acquisition software forming an audit trail. This software is available free of charge from the download section of this website.
Readings may also be simultaneously output to a printer and/or sent to LIMS in CSV format. An Excel workbook that enables reading data to be collected directly into Excel, is available from the downloaded section of this website.
One other important feature is that statistical measurement in accordance with USP may be obtained by a simple print function. Five random samples from a single batch may be applied at a specified interval, measured, removed and the prism cleaned with the MEAN subsequently reported as part of a single experiment.
Radio
Frequency Identity (RFID):
Uniquely, rapid identification of users may now be processed by a
simple radio receiver at the front of qualifying instruments5. Three
tags are supplied with the instrument that can be programmed in accordance
with the level of access granted to any named user as part of the installation
wizard or set-up menu with further packs available as optional extras.
Up to 50 users may be assigned with different access rights. Functions
such as measurement, calibration and configuration are then only granted
when the tag is swiped across and the user recognised.
Manipulation of stored data may also be simplified by use of RFID.
Security Features -
FDA Regulation 21 CFR Part 11:
Strict controls within the pharmaceutical industry
dictate the need for high levels of security in terms of sample analysis
and data control. Instrument software facilitates the level of security:
low, medium and high. The lowest level requires a 3-digit PIN to access
determinable parts of the instrument menu, whilst ‘medium’ requires
an 8-digit PIN. In either of these modes, setting the supervisor PIN
to zero allows free access to all users.
The highest standard of security is compliant with the technical requirements of FDA regulation 21 CFR Part 11, where access to measurement and data transfer is strictly controlled, making use of extended passwords and electronic signatures that have a controlled schedule of validity and re-usage. Changes to the instrument configuration are also recorded in the instrument as an ‘audit trail’ that also records calibration activity, all of which may be extracted using PC software.
The highest level of security facilitating operation in FDA regulated environments is an optional extra on the RFM300+ series of instruments and the new Pro-Juice refractometer.
Calibration:
Two-point calibration in any selected scale allows
accurate control of measurement. Typically ZERO or low-point calibration
is made with water. However,
unlike other manufacturers’ instruments where only water
may be used, all Bellingham + Stanley laboratory refractometers allow
zero calibration with liquids other than water. This feature is particularly
important for calibrating refractometers over a narrow range high up
the RI scale or for calibration at elevated temperatures, where water
becomes unstable near its boiling point. Additionally, legislation within
the pharmaceutical industry dictates use of Certified Reference Material’s
as part of a validation, in which case a low value AG fluid that has
superior traceability than water may be a more suitable option for setting
the zero point. This feature is also useful on the polarimeter where
a number of optically active samples are introduced to a solvent, where
the zero may be set at each step in order to see the effect on optical
rotation as each element is introduced.
SPAN, or top-end calibration, facilitates control at the upper end of the scale at any selected point above ZERO but ideally at the upper limit of the measurement scale of the samples under test.
Please note that Bellingham + Stanley refractometers do not require three or multi-point calibration. Verification at a mid-point should in all cases show the instrument to be performing within its measuring specification. No further calibration is therefore necessary. In the unlikely event that after calibration, the refractometer is not performing within specified tolerances and after repeating the procedure, contact Bellingham + Stanley or an approved service centre. Also worthy of note is that for optimum performance, calibration points should be at opposite extremes of the measurement range with the lowest value used to set zero and the highest to set span.
Automation:
Qualifying instruments provide both mechanical and electrical connection
to other instruments and automated systems. A micro flowcell provides the
connection for pumped sample from an autosampler in beverage and fragrance & flavours
systems, whilst funnel flowcells give rapid readings in busy sugar laboratories.
Full details of automated systems are available on request.
Certified
Reference Materials:
Bellingham + Stanley supply a wide range of UKAS
certified calibration materials manufactured in accordance with EN ISO/IEC
17025:2005 and traceable to International Standards² suitable for
use in the verification procedure of any make or model of refractometer
or polarimeter at 20 °C.
Additionally, software on this website allows refractive index values of CRM’s at other temperatures to be instantly displayed allowing rapid calibration at elevated temperatures³.
PC
Software:
As discussed throughout this section of the website, all instruments
manufactured by Bellingham + Stanley are supported by a range of PC
software programs that allow the user to perform a number of external
functions. Creation of user scales and temperature co-efficient is
made easy, whilst extracting audit trails is an important procedure
for pharmaceutical industries under FDA regulation. All PC software
is available free of charge from this site as a value-added item offering
a measurement solution without any high cost hidden extras!
Digital Models Overview
