MODEL S

PRECISION PLATINUM RESISTANCE THERMOMETER STANDARDS

Model 'S' Precision Platinum Resistance Thermometers have stainless steel sheaths designed for
temperature measurement in laboratory or industrial applications and for general purpose calibration
of resistance thermometers, thermocouples or thermistor probes, in the range -100 degC to +450 degC
They can also be used for in-situ verification of process conditions or instrumentation loops and are of
particular interest to users of precision electronic digital measurement systems, who wish to extend
their capability to the accurate measurement of temperature.

Three models are available, with different ALPHA values, which allows selection of characteristics most suited to a particular application. The nominal resistance value
at 0 deg C (R0) is 100 ohms for each model.

Each thermometer is identified with coding information and serial number.
However, when ordering it is recommended that the full Model number is used.
SDL would be pleased to quote to Customers requiring special thermometers, a high temperature capability, alternative characteristics or mechanical designs.




The Model 'S' will be supplied with 2 metres of cable as standard, and terminated using individual spades.

TECHNICAL INFO

Model: S385 S390 S391

Temperature Characteristics (W Value): 1,3850 1,3900 1,3916
Operating temperature: -100 to +450 deg C
Element: 100 +/- 0,05 ohms
Internal Leads: Four - wire platinum
External Leads: 4-leads of silver plated copper wire, 19/0,15mm, PTFE insulated with outer screen with PTFE cover, fitted with 4 spade connectors and spade connected to screen .
Performance: Each thermometer is supplied with a certificate giving resistance
Guarantee: values as requested by the customer, and obtained by comparison calibration against NPL certificated standards.
Reproducibility: +/- 0,02 deg C or +/- 0.008 ohms
Measuring current: 1 milliampere is recommended
Immersion depth: 200 mm is recommended minimum
Immersion Effect: Approximately +/- 0.005 deg C when changing from 100 to 250mm immersion
Handle temperature: 85 deg C maximum. Do not immerse beyond the sheath marking if using at 400deg C or more.
Material: 316 stainless steel sheath, with a Nylotron handle Sheath dia; 6,35 x 450mm
Handle: 115 x 25mm (nominal)

CALIBRATION OF MODEL 'S' THERMOMETERS

Each thermometer will be calibrated as requested by the customer, at temperature's offered below.

a) Calibration at the Triple Point of Water (t90 = +0.01 deg C)
b) Calibration at Freezing Point of Tin (t90 = 231.968 deg C)
c) Calibration at Freezing Point of Zinc (t90 = 419.58 deg C)
d) Bath Calibration between -85 deg C and 450 deg C
e) Provision of a calibration print-out over requested temperature range and intervals, giving resistance values derived from measurements at 0 deg C , 100 deg C and an assumed value of Delta.
f) Provision of a print-out of W values in 1 deg C steps, using the calibration values obtained at 0degC , 100 deg C and Zinc Point.
g) Sensing Devices Ltd are able to calibrate against standards traceable to NPL, and to
certificate the results with a UKAS accredited certificate.
h) A protective case is provided and recommended for transit and storage of the
Thermometer.

Please direct your orders and enquiries to:-
SENSING DEVICES LIMITED, 97 TITHEBARN ROAD, SOUTHPORT, PR8 6AG
TEL: (44) 0 1704 546161 FAX; (44) 0 1704 546231 email: sales@sensing-devices.co.uk