Our TTI range use high quality ‘Lemo’ connectors for the Pt100 inputs. This simple accessory provides 4mm Terminal Posts for the connection of bare wires, spade terminals or 4mm plugs – useful if a lot of probes are going to be used with the instrument. The adaptor connects to the TTI via two flexible cables, terminated with the appropriate Lemo connector. There are two models, one for the TTI-7, TTI-10 or milliK and a second for the TTI-22....

The TRU 937 (Temperature Reference Unit) supplies a stable and accurate 0°C or elevated Reference Temperatures between 45°C and 70°C. It is a self-contained all solid state unit using peltier technology which provides maintenance free operation. The TRU 937 features rapid cool down from high ambient temperatures and is stable within 10 minutes from switch on. An alarm will be activated should the reference temperatures deviate by more than the user definable span. Thermocouple Reference Junctions are located in a reference block and connected to their marked input and output terminals in an isothermal enclosure. The uniform temperature throughout the enclosure ensures that no thermoelectric EMFs are generated at the terminals. One advantage of the TRU 937 is that the user need not be concerned with the supply and installation of reference junctions since it is only necessary to connect the thermocouple compensation cables to the input terminals and the measuring instrument to the output terminals of the TRU 937. There are two models, the TRU 937/50 with up to 50 junctions with a single terminal cover door, and the TRU 397/100 which has doors on the front and rear, as shown in the photograph....

The TRU (Thermocouple Reference Unit) supplies a stable and accurate 0°C, or elevated reference temperature. It is a self-contained all solid-state unit using Peltier technology which provides maintenance free operation. The TRU features rapid temperature shift even from high ambient temperatures and is stable within 10 minutes from switch on. An alarm will be activated should the reference temperature deviate by more than 0.2°C. The 938 can be ordered with a choice of one of two block types. B1 is recommended for laboratory use and has 6 pockets 6.2mm x 130mm deep and a 4.2mm pocket and can accommodate up to 36 junctions. Block B2 is for higher capacity applications and can accommodate up to 100 junctions with 8 8.2mm pockets x 76mm deep and a 4.2 pocket for an optional monitoring PRT....

Thermocouple Reference System The TRUrac is a 0°C or elevated temperature thermocouple reference system mounted in a 19” chassis. It has been developed for situations where ambient temperature can be up to 65°C. The reference temperature is normally set to 0°C or between 45°C and 70°C. For other temperatures please contact Isotech. An alarm will be activated should the reference temperatures deviate by more than 0.2°C. High Capacity – up to 200 Thermocouple Junctions Inside the rack case is a high stability thermal block which has a capacity of up to 100 thermocouple channels, the probe wires being terminated at the rear of the unit on rail mounted screw terminals. To special order a second thermal block may be fitted to allow a capacity of 200 channels in a single unit. The customer simply connects their thermocouple wires and copper output wires to these terminals. All the thermocouple cold junctions are inserted into a metal oven block which is accurately temperature controlled....

Designed to pre-warm and anneal Standard Platinum Resistance Thermometers Maintenance Free Use Automatic Temperature Cycling The Annealing Furnace, model 414, is designed to heat, anneal and cool Standard Platinum Resistance Thermometers (SPRTs) prior to calibration. The temperature range of the Furnace, from ambient to 1000°C, enables all types of SPRTs to be annealed. One of the duties of a calibration laboratory manager is to ensure that the SPRTs used in the Laboratory are fully annealed and still within specification. Just using the thermometers within the laboratory will cause work-hardening to take place within the platinum coil of the SPRT. Therefore regular annealing is required to ensure the SPRTs are in an ideal condition. In 1990 the then new temperature scale ITS-90 specified the use of SPRTs up to the Silver point (961.78°C). At these temperatures quartz is very porous and in reducing atmospheres the SPRTs can quickly become contaminated. The Isotech Annealing Furnace offers a safe solution for those who wish to anneal SPRTs up to 1000°C. To prevent contamination at high temperatures a constant flux of pre-heated air passes over the SPRTs being annealed. A comprehensive handbook accompanies the Furnace. The furnace has been upgraded to benefit from the latest technology. Fitted with a crystal clear colour display the furnace is now fully programmable. Programs can be created for the cycling of SPRTs – with the ability to set the dwell time at the annealing temperature and heat up and cool down rates along with the number of temperature cycles. Multiple programs can be stored – each with up to 25 segments. The furnace heat up cool down history is logged and can be exported to a USB drive. The PID control parameters are now dynamically optimised at different temperatures optimising furnace stability. This Furnace is installed easily and requires no maintenance....

Heat Pipe Furnaces Isotech metrology furnaces have more than 35 years of proven use and are widely used by the worlds’ leading NMIs. For the optimal use of fixed point cells the temperature uniformity should be less than 10mK over the length of the fixed point sample CCT/2000-13, “Optimal Realization of the Defining Points of the ITS-90…” Isotech heat pipe furnaces offer essentially gradient free operation; heat pipes provide the ideal conditions for the creation and maintenance of ITS-90 fixed point cells. Unlike some other companies Isotech can provide heat pipe furnaces to suit Indium, Tin, Zinc, Aluminum, Silver and Copper fixed points. Plateau length is determined by the difference in temperature between the heat pipe and cell – this can be adjusted to give a plateau of any length of up to tens of hours. Our controllers offer extra resolution and allow adjustment to 0.1°C right up to 1090°C. The Potassium and Sodium models have a cooling coil in the lid with connections to circulate tap water to keep the furnace lid cool protecting the SPRT and reducing heat load into the lab. A pre warming tube with a temperature approximately equal to that of the heat pipe made of a unique and gas-tight material, is provided to heat the SPRT prior to it being placed in a cell. The furnaces feature an adjustable independent and adjustable over temperature device to protect expensive cells and SPRTs as well as a second internal over temperature safety device. Dual Furnaces In addition to the heat pipe furnaces described the Dual Furnaces incorporate a second furnace which, because of its unique design, will safely (and without contamination) pre and post-condition the thermometers. There is also a separate storage enclosure for up to four thermometers with adequate support for the thermometer head. With the Dual Furnace the thermometers are removed from their storage enclosure and placed in the pre-conditioning furnace. The furnace is slowly heated to the Cell temperature. The ...

Affordable Single Zone Furnace Simple Operation For Indium, Tin and Zinc Cells The Isotech Low Temperature Fixed Point Furnace is designed specifically to realize and maintain the freeze plateaux of Isotech Indium, Tin and Zinc Fixed Point Cells, for calibration of thermometers on the International Temperature Scale of 1990. The Low Temperature Furnace is a single-zone furnace. The recommended procedure for establishing a freeze plateau requires operator attention until the plateau is realized. Following that, the Model 17701 Furnace will maintain the plateau, essentially automatically, for a period of 10 to 12 hours. The furnace core, into which the freeze-point cell is inserted, is of aluminium alloy, which provides a very low thermal gradient along the core length. The main furnace heater is of the parallel-tube design as used at NIST. A pre-warming tube is provided. Two entirely independent over-temperature safety devices are included. A dedicated (on-off) over temperature control circuit provides active safety. A fusible link in the main power circuit provides passive safety. The Low Temperature Furnace is completely self-contained, castor mounted and requires no external supplies (except power). New Features From our own ongoing experience and customer feedback we have updated the Isotech Furnace Range to deliver the same proven performance and advanced features but with a number of convenience upgrades to make your life easier. The controllers have now been relocated to the top for easier operation, we now include an SPRT Stand and Cable Tidies to keep your standards safe and Accessory Pods to keep the furnace tops free from clutter. Our furnaces are programmable to automatically melt and freeze cells and feature both USB and Ethernet interfaces with bright crystal clear displays....

Whilst heat pipe furnaces offer the ideal environment to melt and freeze ITS-90 Fixed Points the temperature range is limited by fluid that flows inside the pipe. Three zone furnaces can offer wider operating ranges and still meet the requirements for “Optimal Realization of the Defining Points of the ITS-90…” CCT/2000-13. In place of a heat pipe the 17703 Medium Temperature furnace uses top and bottom guard heaters to minimise temperature gradients. The Model 17703 Furnace can be used with Indium, Tin, Zinc and Aluminium Cells. The substantial furnace core is machined from aluminium bronze. New Features From our own ongoing experience and customer feedback we have updated the Isotech Furnace Range to deliver the same proven performance and advanced features but with a number of convenience upgrades to make your life easier. The controllers have now been relocated to the top for easier operation, we now include an SPRT Stand and Cable Tidies to keep your standards safe and Accessory Pods to keep the furnace tops free from clutter. Our furnaces are programmable to automatically melt and freeze cells and feature both USB and Ethernet interfaces with bright crystal clear displays....

The Isotech Model ITL-M-17725 apparatus is a self-contained, mechanically-refrigerated, system with a main well to house one mercury cell and two auxiliary wells for pre-chilling of thermometers. The cryostat temperature is adjustable from -36°C to -42°C. It makes the operation of mercury cells simple and safe. The cryostat has several unique features providing outstanding convenience and safety. The refrigeration system has sufficient capacity to bring a cell to operating temperature in about one hour. At operating temperature, the cooling rate is about 1 Kelvin/minute and the heating rate is about 2 Kelvin/minute. This permits rapid changes to be imposed on the temperature of the cell environment to avoid excessive demands on the (low) heat-of-fusion energy of the mercury within the cell. In addition, all temperature control is accomplished through control of refrigerant flow, providing inherently fail-safe operation. The cryostat provides convenient conditions for operating mercury fixed point cells both in heating and in cooling mode. The apparatus has a long and successful history and has been relied on by many National Laboratories throughout the world for over 35 years. The control system has been updated with the latest technology and now features a large colour display with crystal clear graphics. An Ethernet interface allows the bath temperature to be remotely monitored. Other features include a program option to allow switching between melt and freeze temperatures. A USB Interface allows programs to be copied or for apparatus heat up and cool down history to be exported....

The fundamental problem with surface temperature measurement is that it is subject to large stem conduction errors, also because heat conducted from the surface of the hot-plate causes a localised cold spot to be created which means that the temperature indicated by the hot plate is not necessarily the temperature at the point of measurement. An ideal system would not disturb the heat-flux from the hot-plate. During 1993 such a system was described (ref. “Progress in Contact Thermometry” 1993 B. D. Foulis) and Isotech have the inventor’s permission to make and market the device World-wide. Principal of Operation A fine wire type N thermocouple is used as the surface temperature sensor, a second junction 2 to 3mm along the thermocouple, senses the temperature difference due to heat flux along the sensor. A heater heats the thermocouple stem until the temperature gradient is zero, thus creating a measurement without stem conduction, or disturbance of the hot-plate’s surface. The 944 can be used with the Isotech Small Hot Plate model 983. A traceable calibration certificate is available to order....

Whilst heat pipe furnaces offer the ideal environment to melt and freeze ITS-90 Fixed Points the temperature range is limited by fluid that flows inside the pipe. Three zone furnaces can offer wider operating ranges and still meet the requirements for “Optimal Realization of the Defining Points of the ITS-90…” CCT/2000-13. In place of a heat pipe the Model 465 3 Zone High Temperature Furnace uses top and bottom guard heaters to minimise temperature gradients. This more recent addition to our long-established range of metrology furnaces offers an alternative for those who prefer 3-Zone furnaces to heat pipe technology and need high temperature operation. The three zones create a controlled volume of constant temperature within the furnace in which High-Temperature Fixed Points such as Aluminium, Silver and Copper can be frozen and melted. Because High-Temperature thermometers can be easily contaminated by metallic vapors, great care has been taken to eliminate the use of metals throughout the calibration volume. The cell holder is made of alumina. A ceramic equalizing block is available comprising a closed ended tube, alumina tubes to house the sensors being compared, and alumina powder to act as an equalizing media. This 3-Zone Furnace can be used for the realizations of Zinc, Aluminium, Silver, Gold and Copper points, or with an optional equalizing block used for annealing or comparison calibration. New Features From our own ongoing experience and customer feedback we have updated the Isotech Furnace Range to deliver the same proven performance and advanced features but with a number of convenience upgrades to make your life easier. The controllers have now been relocated to the top for easier operation, we now include an SPRT Stand and Cable Tidies to keep your standards safe and Accessory Pods to keep the furnace tops free from clutter. Our furnaces are programmable to automatically melt and freeze cells and feature both USB and Ethernet interfaces with bright cr...

This dedicated apparatus has more than 35 years of proven use and is widely used by the worlds’ leading NMIs. In a recent International study cells from 21 of the world’s leading laboratories were inter-compared; the study used two Isotech 18233 Baths to maintain the cells during the inter-comparisons. The Isotech Model 18233 Water Triple Point Maintenance Bath is not an adaptation of general-purpose equipment, but is specifically designed to maintain and safeguard one to four Water Triple Point Cells. Cooling is accomplished by efficient solid-state Peltier chilling modules, powered so that the rate of temperature change is very small. Solid state cooling ensures minimal power consumption, silent operation and no vibration. Safety is provided by both electrical safety circuits and passively by the physics of ice. If the Peltier chillers become too cold, the first ice which forms is on the water tank surfaces directly in contact with the chillers, effectively inhibiting further rapid transfer of freezing to the bath water. Compared to general purpose baths with mechanical cooling it has advantage of Safer Operating Range -0.3 to +0.3C Solid State Vibration Free Cooling – Quieter Operation Holds up to Four Cells Lower Energy Consumption / Operating Costs Updated Control System The control system has been updated and now features a large colour display with crystal clear graphics. An Ethernet interface allows the bath temperature to be remotely monitored. Other features include data logging of the bath temperature along with the air intake temperature – the data can be exported to a USB drive. The bath has a long and successful history and is relied on by many National Laboratories throughout the world. This history of successful use is one of the most important reasons for choosing Isotech products....