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Thermocouple Calibration Sphere, Model Saturn 877
Isotech, Spherical Thermocouple Calibration Furnace
Spherical Designed Thermocouple Calibrator: 100°C to 1300°C (2372°F)
  • Accuracy: ±0.25°C at 1000°C
  • Stability: Spherical design provides unmatched stability and uniformity
  • Uniformity: Central zone of zero heat flux
  • Used internationally by NMIs, thermocouple manufacturers and the best calibration labs

Product Code: 877

   Product Description

Thermocouple Calibration Furnace

Thermocouple Calibration Sphere, Model Saturn 877

The Saturn spherical furnace comprises a number of concentric shells. The outer shell of spun metal is for containment and support. Inside this is a layer of ceramic fiber. Within the fiber is a ceramic spherical mantle containing the heater windings. In the centre of the furnace is a solid cast ceramic sphere with 8 or 16 tubes, to be used for the thermocouples requiring calibration.

Isotech's calibration furnace is revolutionary from a number of aspects:

It is spherical, and its design ensures a central zone of constant temperature.

Thermocouples are inserted around the circumference of the furnace. When fully inserted the measuring junctions are within a few millimeters of each other at the center of the sphere.

Up to 15 thermocouples can be calibrated simultaneously. The accuracy is between ±0.25°C and ±0.1°C at 1000°C.

Larger tube diameters will give larger gradients, as will larger numbers of tubes. The precision of this furnace has previously been achieved only by using heat pipes.

Because of the design the price is only one half to one third that of a bath with comparable accuracy and much smaller capacity of calibration.

The use of newly developed modern ceramic materials has enabled high accuracy, low mass and high stability to be obtained. The Saturn system will not contaminate your thermocouples unlike some furnaces that have metal equalizing blocks.
Model 877
temperature Range 100°C to 1300°C
Number of Calibration Points 8 as standard
16 to special requirements
Diameter of Sensors 4 x 6mm + 4 x 8mm
Depth of immersion 180mm
Accuracy ±0.25°C to ±0.1°C at 1000°C
(using comparison techniques.)
Warm-up times* 1 hour to 700°C 3 hours to 1300°C
Stabilisation time* 1 hour to ±0.25°C
Communications Supplied as standard with serial interface. PC adaptor cable, and Cal NotePad.
Power 3kW, 208-240Vac, 50/60Hz
3kW, 115Vac, 50/60Hz
Dimensions 425 mm Diameter
Weight 25 kgs
988/01 Equalising Block 4 x 8mm + 4 x 6mm i.d. (standard)
877/01S Equalising Block 16 x 6mm (special
977/01E Equalising Block - Other configurations (consult Isotech
877/02 Platinum Foil Temperature Barrier
* These time may increase as the windings age or if the supply voltage is low.


to special order, the following opetions are available, please contact Isotech for details.

1. 16 Thermocouple Inserts. Because of the extra thermal mass involved in offering this option, an extra 30 minutes should be allowed for full stabilisation.

2. Larger Thermocouple Inserts. Inserts of up to 10mm (0.4 inches) diameter can be accommodated in the furnace. Please consult Isotech.

3. Platinum wrap can be fitted. Isotech wrap the insert of the Saturn in Platinum foil. Reducing the gradient at 1000°C to an unmeasurable value (less than 1μV difference from 2 type R Themocouples).

4. Blackbody Option.


Saturn 877 Spherical Furnace Datasheet Saturn 877 Spherical Furnace Manual
877 Saturn Datasheet 877 Saturn Manual

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