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Supplementary installation, operating and maintenance instructions English
Explosion-proof three-phase asynchronous motors with squirrel-cage rotor for high voltage
815001 Edition 09.2020
11
2. Information about ignition pr
otection type increased safety “eb”
2.1 Protective principle/labelling
Ignition protection type in which additional measures are taken to prevent the possibility of impermissibly
high temperatures and the occurrence of sparks or arcs during normal operation or under specified excep-
tional conditions with an increased degree of safety.
Prevention of sparks and other ignition sources
Enclosure at least IP54 for bare, live parts inside
Enclosures at least IP44 if all live parts inside are insulated
Observance of creepage and clearance distances
Special attention to insulation materials and seals
Temperatures of the outer and inner surfaces
must be lower than the ignition temperature both in normal operation and in the event of a fault (mo-
tor stalling)
Protection devices (temperature monitoring and/or
overcurrent switch with I
A
/I
N
-tE time characteristic) required for the user
Frequency inverter operation see section 3
Tests:
Insulation test
Temperature measurement for defined faults
Additional tests for certain equipment (TMS full protection)
Areas of application:
Equipment zone 1 and 2, category 2G and 3G (Gb,Gc)
Marking of the motors with EC Type Examination Certificate according to Directive 2014/34/EU (94/9/EC):
CE 0637
II 2 G Ex eb IIC T1/T2 or T3 Gb
QA certification by NB 0637 ... IBExU Freiberg
For explosion-
proof motors in ignition protection type increased safety “eb” according to IEC/EN 60079–0
and
IEC/EN 60079
–7, the following points must be observed in particular:
The greater danger in potentially explosive atmospheres requires particularly careful attention to the safety
and commissioning instructions. Explosion-proof motors may only be used in potentially explosive atmos-
pheres in accordance with the regulations of the responsible supervisory authority. It is responsible for deter-
mining the explosion risk and zone classification. Ignition protection type, temperature class and special re-
quirements are stated on the rating plate or on the EC Type Examination Certificate. If the certificate number
ends in an X, special conditions on the EC
Type Examination Certificate must be observed. Electrical
machines fall into this category, e.g. also those with ignition protection type increased safety “eb” for inverter
operation.
2.2 Information about impermissible heating
Unless otherwise stated on the test certificate or the rating plate in connection with operating mode and toler-
ances, electrical machines are designed for continuous operation and normal, not frequently recurring starts
during which no significant start-up heating occurs. The motors may only be used for the operating mode in-
dicated on the rating plate. If the operating mode is not indicated on the rating plate, the motors may only be
operated in continuous operation, S1.
The voltage and frequency limits of area A in IEC/EN 60034-1 (DIN VDE 0530, part 1)
– voltage
5%, fre-
quency
2%, curve shape, mains symmetry
– must be observed so that heating remains within the permissi-
ble limits. Larger deviations from the rated values can increase the heating of the electrical machine inadmis-
sibly and must be indicated on the rating plate. The motor must be protected against impermissible heating
during start-up, e.g. with a motor protection switch, i.e. impermissible heating must be prevented in all
phases by a current-dependent delayed circuit breaker according to DIN VDE 0660 or an equivalent device.
The protective device must be set to the rated current. Windings in delta circuits must be protected in such a
way that the triggers or relays are connected in series with the winding strands. Selection and setting of the
triggers is based on the rated value of the strand current, i.e. 0.58 times the rated motor current. If a circuit of
this sort is not possible, suitable circuit breakers, e.g. with phase failure monitoring, must be used. For pole-
changing motors, current-dependent delayed triggers or relays must be provided for each speed level and
must be locked out from each other.
With ignition protection type increased safety “eb”, the start-up is also monitored. The protective de-
vice must therefore switch off within the t
E
time specified for the respective temperature class if the
rotor is blocked. The requirement is met if the tripping time - which can be taken from the tripping