H981 Temperature Measurement Methods and Calibration Unit

H981 Temperature Measurement Methods and Calibration Unit

The measurement of temperature is fundamental to almost every branch of engineering and science.

The H981 enables students to investigate the many different methods of measuring temperature and to determine the advantages and disadvantages of the various sensor and indicator types.

Up to nine different methods of temperature measurement are included and students undertake detailed experiments to compare not only accuracy but also the way in which the instruments work. The operation of platinum resistance temperature sensors and their importance in the International Temperature Scale (ITS-90) are investigated in detail.

Optional computerized data acquisition and traceable calibration standards are also available and add to the extreme versatility of this unit.

H981 Temperature Measurement Methods and Calibration Unit

The unit is supplied with a detailed experimental operating and maintenance manual giving example experimental results and sample calculations.

Accessories and spares for two years normal operation together with a full two year warranty are also included as standard.

A bench top control console with accurate platinum resistance thermometer (PT100), thermistor indicator, thermocouple indicator with selector switches and an accurate millivolt meter.

All electronic indicators include re-transmission signals for use by user supplied chart recorders, data acquisition systems or an optional 35 channel data acquisition system with menu driven software which can be supplied by P.A.Hilton Ltd.

The panel includes connection points for detailed investigation of thermistor and platinum resistance temperature sensor (PT100) resistance variation with temperature and investigation of 2, 3, and 4 wire connection methods and associated errors. A constant current source allows detailed examination of the PT100 probe method of operation. Investigation of the International Temperature Scale (ITS-90) and the reference PRT equation may be undertaken. A temperature controlled heater and stainless steel vacuum flask allow calibration of all instruments relative to the accurate platinum resistance (PT100) thermometer and fixed points. An optional dry well calibrator with optional traceable UKAS/NAMAS calibration is available.

A high accuracy amplifier and digital voltmeter allow investigation of at least 3 types of thermocouple including  series and parallel connection, the law of intermediate metals and temperatures and cold junction reference.

Additional temperature measuring devices include liquid in glass thermometers, bi-metallic, vapour pressure and reversible liquid crystal indicators.

All small ancillary items are retained in an aluminium case for security.

  • The use of (expansion) liquid in glass thermometers for measurement of fixed scale points.
  • The use of vapour pressure for temperature measurement.
  • The use of bi-metallic expansion devices for temperature measurement.
  • The Peltier and Seebeck thermo-electric effects.
  • Investigation of junction voltage from different thermocouple types.
  • The use of ice point reference with a thermocouple. 
  • The law of intermediate metals and intermediate temperatures associated with thermocouples.
  • Voltage calibration of different thermocouple types using a water-ice reference.
  • The effect of lead resistance and voltmeter meter impedance on thermocouple measurements.
  • Use of a direct reading, internally compensated thermocouple indicator.
  • Connection of thermocouples in series for signal amplification and parallel for averaging of measured temperatures.
  • Investigation of the response rate of various thermocouples and sensors.
  • Investigation of the platinum resistance sensor (PRT), its resistance change with temperature and the reference PRT equation of ITS-90.
  • Investigation of the use of 2, 3 and 4 wire PRT sensor connection and the error effects of lead resistance.
  • The use of a direct reading PRT indicator device.
  • Investigation of the resistance change of a negative temperature coefficient thermistor sensor with temperature.
  • The use of a direct reading thermistor indicator device.
  • Calibration of all of the supplied sensors with reference to an accurate platinum resistance thermometer (PT100)



A:  220-240 Volts, Single Phase,50Hz (With earth/ground).

     Line current up to 2.5A at 230v


B:  110-120 Volts, Single Phase, 60Hz (With earth/ground).

     Line current up to 5A at 110v