SIEMENS
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Siemens D 83.1 · 2016
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Motors with Explosion Protection
SIMOTICS XP 1MD5 motor series
General information
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Technical specifications
(continued)
Electrical design
The insulation system of the SIMOTICS XP 1MD5 motor series is
suitable for line voltages up to 690 V. The connection system
(terminal box, terminals) is also designed for this rated voltage.
The explosion-proof motors are equipped with 6 terminals. They
can thus be operated in star or delta. If a voltage variant with
dual voltage e.g. 400 V
/690 VY is selected, the rated data of
both voltage levels will be stamped on the rating plate.
The motors in the SIMOTICS XP 1MD5 series are manufactured
with an insulation system of thermal class 155 °C. Utilization at
rated operation corresponds to thermal class 130 °C.
Operation on a frequency converter
The general use of high-quality insulation systems enable
operation on a frequency converter.
The permissible speed and torque range is stamped on an
additional rating plate.
For operation on a frequency converter, the motor with explosion
protection must be fitted with PTC thermistors. These are
installed in the stator winding and, in combination with a certified
trip unit (EU type examination certificate), they perform sole
motor protection in the case of converter operation. Motor circuit
breakers can be dispensed with.
Line operation
Motors operated directly on the line must be protected, e.g. by a
suitable motor circuit breaker. Alternatively, motor protection using
a PTC thermistor for full motor protection (sole protection) may be
selected on request. As the load case "blocked shaft, motor draws
full starting current" also has to be monitored, this version cannot
be used consistently.
The larger the motor and the smaller the number of poles, the
more difficult it is to achieve sole protection using PTC thermistors
in line operation. Due to the laws of increasing size, larger
machines become ever more "rotor-critical". The sole protection
limit for 4-pole motors typically lies in the region of frame size 280.
Voltage tolerances
The motors are suitable for operation with voltage and frequency
tolerances according to EN 60034-1.
In addition, tests are to be performed to ensure that the
permissible temperature limits for the outer surface of the
explosion-proof enclosure according to EN 60079-1 are not
exceeded during continuous operations at the voltage limits
(± 10%).
The motors in the 1MD5 range in this catalog are certified for T4.
The maximum permitted surface temperature is 135 °C.
© Siemens AG 2016