Table des Matières
Publicité
C.4
Données
R-No. 20000h
INVERTER OPERATION OF EXPLOSION-PROTECTED LOW VOL TAGE THREE-PHASE MOTORS IN
PROTECTION TYPE FLAMEPROOF ENCLOSURE AND PROTECTION TYPE N (NON-SPARKINGl FOR THE
Inverter operation of explosion-protected motors is allowed, when the following requirements are met:
I. The output voltage of the inverter is to be adjusted in such a way that in the frequency range up to the rated frequency
of the motor an almost linear relationship between the (fundamental) voltage and the (fundamental) frequency is kept,
i.e. the practically constant motor tlux must be kept in accordance with the rated data.
Motors operating above the 1. 1 fold rated frequency are only permitted if a corresponding rating plate for inverter
operation is fixed on the motor.
2. IcOflti'l. is the value to which the inverter management limits the current in continuous duty.
Icontin.
for inverter operation attached to the motor or in conformity with the value detennined in the describing documents for
inverter operation (R-No.).
3. l'hO<l is the value to which the inverter management limits the eurrent in case of a short-time overload for a period of
max. tshon-
I s hon
t s h o rt is the period for which the inverter allows an exceeding of
4.
t shon is to be adjusted to 60 s at a maximum.
5. The built-in temperature sensors (PTC thermistors) which must be suitable for sole protection are to be connected to a
tripping device provided with the EC type examination certificate, like e.g. CK140: PTB 04 ATEX 3038 or CKI44/145:
PTB 02 ATEX 3059, according to Directive 94/9/EC.
6 . Voltage peaks (especially for PWM inverters with long motor cable)
a) The design of the terminal box conceming the air and creepage distances allows the inverter operation with
b) To avoid the formation of partial discharges it is required for Ex nA machines that the
Ruhstorf, 20 12-09-10
J:\LGR08\QM\QME\PrOffeld\FORM\r·nr\r·nr.20000h_EN.doc
SIMOTICS XP 1MD5
Instructions de service 03/2014
Siemens Aktiengesellschaft
Postfach
D-94095 Ruhstorf
is to be adjusted to the continually pennitted motor rated current as a maximum in accordance with the rating plate
Icontin.
is to be adjusted to 1 . 5 x
at a maximum.
(OLL
voltage peaks
�Maximum value of the conductor-to-conductor voltage and
0
line-to-earth voltage) up to
� 1866 V which is not allowed to be exceeded for explosion protection reasons.
is limited, depending on the rise time to values which are below the characteristic curve of the chart "Dielectric
strength curve" (see diagram below). In order not to limit the service life this is recommended for Ex d motors.
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TEMPERATURE CLASSES TI-T4
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SIEMENS
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Maximum value ofthe
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Siemens Aktiengesellschaft
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Dr. Klaus Neupert
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Documents qualité
C.4 Données
129
Publicité
Table des Matières
