Siemens SIMOTICS XP Operating Instructions Manual page 96

Operation
8.1 Safety instructions for 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.
Risk of explosion due to excessive bearing temperature
The surface temperature cannot be maintained within maximum permissible limits if the
bearing becomes too hot. The dust can ignite, resulting in an explosion. This can result in
death, serious injury or material damage.
• Monitor the bearing temperature (Page 87).
• In addition to the current-dependent overload protection device located in the three
phases of the connecting cable, we recommend that you also monitor the temperature
rise in the machine using temperature sensors integrated in the stator winding.
94
1MB..5/6 shaft height 71 ... 355
Operating Instructions, 10/2021, A5E41926185A