Protection Of Explosion-Proof Motors - Siemens SIPROTEC 5 7UM85 Manual

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Protection of Explosion-Proof Motors

For installing the equipment in an explosive environment, the standard EN 60079-14 or the standard
VDE 0165, part 1 (electric equipment for hazardous areas) must be observed.
The preceding standards require the overload protection for cage-rotor asynchronous motors (see also
EN 60079-7, Appendix A). The device 7UM85 provides this protection if the following requirements are met:
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The rated current of the motor must be set on the 7UM85.
•
The operate curve must be selected so that for locked-rotor current, the tripping time lies within the
locked-rotor time t
NOTE
i
i
In case of heavy starting of the motor that takes more than 5 seconds with a high starting current, this
setting initiates the tripping already during the starting time. In this case, special protection measures must
be taken to prevent the temperature from exceeding the threshold. The special protection measures can be
speed monitoring during motor start and special adjusted setting of the 7UM85.
In the preceding situation, the particular requirements of the conformity declaration of the motor must be
observed. Alternatively, you must contact the manufacturer of the motor for verification of this topic.
•
If the locked-rotor time t
tion must be proved.
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The 7UM85 must be set up outside the hazardous area.
If deviations from the correct function are detected during the commissioning of the device, you must send
the device back to the manufacturer.
SIPROTEC 5, Additional Information on the Protection of Explosion-Proof Motors with Type of Protection Increased Safety e,
Manual
C53000-H5050-C078-1, Edition 03.2019
indicated on the name plate of the motor.
E
of the machine under protection is smaller than 5 s, the efficacy of the protec-
E
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