VERDER CARBOLITE GERO 3508 Series, Инструкции по установке, эксплуатации и обслуживанию

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Operators are advised to periodically check the thermocouple output, either by a
calibration test or by comparing the output with a new reference thermocouple which
has been subjected to high temperatures for a minimum length of time.
Failure to check the thermocouple regularly may result in overheating of the work and
the furnace, with consequential damage to both.
(2) The thermocouples fitted to these models give very low outputs below
approximately 600 °C and do not give accurate readings at low temperatures. They
may show a negative temperature when the furnace is started from cold.
This furnace is not intended to operate with a setpoint below 600 °C.
6.10 General Operating Advice
Heating element life is shortened by overheating. Do not leave the
product at high temperature when it is not required. The maximum
temperature is shown on the product rating label and in section 12.0
towards the back of this manual.
When heating large objects, in particular poor conductors, avoid shielding the
thermocouple from the heating elements. The thermocouple is intended to sense the
temperature near the heating elements. However, if a large object is placed in the
chamber it may record the average temperature of the object and the elements, this
can lead to overheating of the elements. Allow large objects to gain heat at a lower
temperature and then reset the controller to a temperature close to the desired
maximum, or heat using a slowly controlled ramp rate. For more information refer to
the controller instructions.
The product's elements are very susceptible to mechanical shock. Take great care when
loading or unloading the chamber. If it is necessary to load or unload work at elevated
temperatures, keep the door open for as short a period as possible. The insulation cools
quickly and may crack though thermal shock.
For improved insulation and element life it is recommended to heat and cool at a slow
ramp rate e.g. 5 °C/minute, and to avoid opening the door at high temperatures.
On first installing the elements and on subsequent element replacement, operate the
product at 1500 °C for an hour to create a protective glaze on the element surface.
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6.0 Operation