Isotech Saturn 877 Specifications

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SOLUTIONS FOR PRIMARY & SECONDARY LABORATORIES

Thermocouple Calibration Furnace

100 to 1300°C

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Accuracy 0.25°C at 1000°C

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Central Zone of Zero Heat flux

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Range 100°C to 1300°C

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 fibre. Within the fibre 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.

Model 877

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
centre 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 8 as standard
Calibration Points 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

* These times may increase as the windings age or if the

supply voltage is low.

Accessories

877/01 Equalising Block 4 x 8mm + 4 x 6mm i.d.

(standard)
877/01S Equalising Block 16 x 6mm (special)
877/01E Equalising Block - Other configurations

(consult Isotech)
877/02 Platinum Foil Temperature Barrier

How to Order

877 Thermocouple Calibration Facility including Standard
Equalising Block.
Please specify voltage required

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SOLUTIONS FOR PRIMARY & SECONDARY LABORATORIES

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Blackbody Option Thermocouple Calibration

Note:

Spherical furnaces are normally supplied 240 Volts, 50 Hz, 3 kW with 8 sensor
insertion points, one of which is used to house the control thermocouple.
Eight tubes with a nominal internal diameter of 6 mm have been found to give
a very good and stable performance. It is the configuration around which the
specification has been written.

OPTIONS

To special order, the following options 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 Thermocouples).

4 Blackbody Option.

Each thermocouple is completely isolated in a gas
tight closed end tube to prevent any contamination
problems during calibration.

Normally the windings will require replacing after a
few years of operating (dependent on work cycle) and
so the furnace has been designed with ease of
maintenance in mind. A spare set of windings is
provided free with each furnace, as is a
comprehensive handbook.