Use Of Probes; Atmospheres; Operator Safety; Power Adjustment - Carbolite Gero 3508 Installation, Operation And Maintenance Instructions

6.0 Operation
Materials such as case hardening compounds and other reactive salts may penetrate the
furnace chamber lining and attack the wire elements, causing premature failure. Use of
a hearth tile may be advisable: please consult the Carbolite Gero technical department.
6.3

Use of Probes

Any metal object used to probe into the product chamber while the product
is connected to the electrical supply must be earthed. This applies in
particular to metal sheathed thermocouples, where the sheaths must be
earthed. The refractory material of the chamber lining becomes partly
conductive at high temperatures and the electric potential inside the
chamber can be at any value between zero and the supply voltage.
Unearthed probes can cause serious electric shock.
6.4

Atmospheres

When an optional gas inlet is fitted, there is a label near the inlet saying "INERT GAS
ONLY". In practice, inert or oxidising gases may be used, but not combustible or toxic
gases.
The chamber is not gas tight, the gas usage may be high and the chamber is always
likely to contain some air. Residual oxygen of approximately 1% to 2% is to be
expected.
6.5

Operator Safety

This product incorporates a safety switch which interrupts the heating
element circuit when the furnace is opened. This prevents the operator
touching a live heating element and also prevents the product from heating
up if the furnace is left open. The operation of this switch should be checked
periodically.
Depending on use, the surfaces in the working chamber and the chamber
load may still be very hot after the appliance is switched off. Touching these
surfaces may cause burns. Use suitable personal protective equipment or
wait until the appliance cools down to ambient temperature.
Before removing a hot object from the Product, make sure there is a safe place to put it
down. If necessary use tongs, face masks and heat resistant gloves. Heat resistant
clothing and face protection can guard against the effects of radiated heat when the
furnace is open.
When the door is opened during operation there is considerable radiated heat. Do not
keep any flammable objects near the product, nor objects which could be damaged by
radiated heat.
6.6

Power Adjustment

The product control system incorporates electronic power limiting. Depending on the
model and the destination country the power limit maybe set to 100% or a lower figure.
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