Operation
8.1 Safety instructions for operation
1MB..5/6 shaft height 71 ... 355
94 Operating Instructions, 07/2020, A5E41926185A
Explosion hazard if the bridging is removed from the insulated bearing
Removing the factory-fitted bridging of the insulated bearing leads to potential differences
between the rotor and the grounded motor. This can cause the generation of sparks, which
especially in an explosive atmosphere can ignite surrounding dust or combustible gases.
Explosions can occur. There is also a risk of an electric shock. Death, serious injury, or
material damage will result.
• Do not open the bridging of the bearing insulation during operation.
Overheating as a result of the anti-condensation heating
If the anti-condensation heating is operated while the machine is operational, this can
increase the temperatures inside the machine and cause material damage.
• Install an interlock circuit that switches off the anti-condensation heating once the main
machine is switched on.
• Only switch on the anti-condensation heating after the motor has been switched off.
Comply with the data stamped on the plate of the anti-condensation heating, if available.
Explosion hazard from hybrid mixtures
Hybrid mixtures are mixtures of flammable dusts with explosive gas/air atmospheres which
can together create a dangerous explosive atmosphere if they occur at the same time.
Changes can arise in the safety characteristics here, such as a change in the zonal
classification, increase in the explosion pressure, reduction in the minimum ignition energy
and a reduction in the maximum temperatures to be observed.
An explosion can result. This can result in death, serious injury or material damage.
• For this reason, the relative characteristics must be considered both for gas (zones 0, 1
and 2) and for dust (zones 20, 21 and 22) where hybrid mixtures arise. It is necessary for a
competent assessor to determine in the individual case whether the parameters
determining ignition are unfavorably affected in a particular hybrid mixture.
• Motors with dual plates for G (“Gas”) and D (“Dust”) may only be used where these two
occur after prior examination of the properties of the hybrid mixtures by the user.
• Explosion-protected 1MB..5/6 machines are not suitable for hybrid hazardous zones. Use
in atmospheres where there is a risk of explosion caused by both gas and dust
simultaneously is absolutely prohibited.
Explosion hazard due to overheating of the machine caused by a layer of dust
Deposits of dust have a thermal insulation effect, which can lead to the machine overheating.
The maximum surface temperature of the machine cannot be adhered to. The dust can
ignite, resulting in an explosion. This can result in death, serious injury or material damage.
• Dust the machine regularly.
• Do not allow dust layers thicker than 5 mm to build up on the machine surface.
• Do not switch the machine on until the dust has been removed.
To Next Page
Loading...
