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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
15
5.4 Stator housing
The stator housings are made of grey cast iron EN GJL-200 DIN EN 1561 with horizontal-vertical cooling
fins. The minimum wall thickness of the housing jacket outside the centring rim of 9 mm is maintained and
increases towards the core. The strength of the housing construction has been verified using sample types in
an impact test according to DIN EN 60079-
0 for Group II with the mechanical hazard level “high” (test report
03/2014 dated 15.04.2014).
For fixing of the terminal box and terminal base, a surface with a corresponding opening to the interior of the
housing is cast on the housing.
5.5 Stator winding
The winding and insulation design for machines of ignition protection types increased safety “eb” and “ec”
corresponds to an insulation type tested according to EN 60079
–7:2015 section 6.2.3.1 for equipment group
IIC, or the ignition protection type protection by enclosure “tb” for equipment group IIC. The minimum air gap
between the winding head and the enclosure or other grounded parts is at least 15 mm.
5.6 Terminal box, star point box
Terminal boxes are used which have a separate test report in accordance with Directive 2014/34/EU .
5.7 Entry parts
To insert the connection cables, cable glands (or screw plugs) according to 2014/34/EU are used in the
cover plate with a minimum protection class of IP65.
If the terminal boxes are supplied with an undrilled cable entry plate, make sure that only cable entries are
used
- which are suitable in their design and dimensions for the connecting cables
- which correspond to the protection class of the terminal boxes
- which have an ignition protection type approved for the zone and the associated ATEX conformity certifi-
cate
Drill threaded holes in the plate to match the screw size.
When using screw connections with metric threads, through holes can also be used. The screw connections
must then be assembled with locking nuts, taking into account the thickness of the plate. The diameter of
these through holes must be selected in accordance with
DIN EN 50262.
5.8 Standstill heating
In accordance with EN 60079-7, section 5.2.7, the motors are equipped with a standstill heating system as
standard. The heating cables must comply with the requirements of Directive 2014/34/EU. The heating ca-
pacity and supply voltage are indicated on the motor rating plate. Appropriate terminals for auxiliary circuits
are provided to connect them in additional terminal boxes that meet the requirements of Directive
2014/34/EU. They are connected according to the enclosed terminal diagram. The standstill heating is only
to be switched on after the motor has been switched off. It must not be switched on during motor operation.
6. Additional equipment
Explosion-proof motors can be equipped with additional optional equipment that meets the requirements of
Directive 2014/34/EU:
6.1 Additional thermal motor protection
For monitoring the stator winding temperature, temperature sensors (PT100) which meet the requirements of
Directive 2014/34/EU are installed in the motor. Appropriate terminals for auxiliary circuits are provided to
connect them in additional terminal boxes that meet the requirements of Directive 2014/34/EU. They are
used to make the connection according to the enclosed terminal diagram.
6.2 Forced ventilation unit
The forced cooling fans must meet the requirements of Directive 2014/34/EU. The forced ventilation unit en-
sures dissipation of the heat lost during operation of the main motor. During operation of the main motor, the
forced ventilation motor must be switched on.
For motors with forced ventilation units that depend on direction of rotation, the direction of rotation must be
observed. (See rotation direction arrow). Only the forced ventilation units supplied by the manufacturer may
be used. The forced ventilation unit must be connected according to the applicable terminal diagram pro-
vided in the terminal box.
6.3 RFID transponder (memory motor)
There is the option to equip the system with an RFID transponder (for short: TAG) as a memory motor, spe-
cial code MM, according to EW-N 1002, sheet 13. The