Description   
3.3 Installation 
  1LA5/6/7/9, 1LG4/6, 1MA6/7, 1MB..1/2/3/4/5 - SH 63 ... 355 
24  Operating Instructions, 06/2018, A5E44455710A 
Electrical equipment for use in the presence of com-
bustible dust - Part 17: Inspection and maintenance of 
electrical systems in hazardous areas (except under-
EN / IEC 60079-17  GOST 30852 16 - 
2002 
Electrical equipment for hazardous gas atmospheres, 
Part 19: Repairs and overhauls 
EN / IEC 60079-19  GOST 30852 18 - 
Potentially explosive atmosphere - Part 31: Device 
dust explosion protection by enclosure "t" 
EN / IEC 60079-31  GOST R 
Directive on the approximation of the laws of the Mem-
ber States concerning equipment and protective sys-
tems intended for use in hazardous areas. 
Directive 2014/34/EU  TR CU 
 
The machines of this series are three-phase induction machines with a closed primary 
(internal) cooling circuit and an open secondary cooling circuit (surface cooling). The surface 
cooling varies depending on the version.  
 
Machines with a fan 
Self-ventilation (standard): Cooling method IC 411 according to EN / IEC 60034-6 
Located at the ND end of the stator housing is an air intake cowl that guides the external air 
on its way to the motor. The external air is drawn in through openings in the air intake cowl 
and flows axially across the outer cooling ribs of the motor frame. The fan wheel for the 
external flow of cooling air is attached to the machine shaft. 
The fan wheels are bidirectional. 
Check the cooling effect below rated speed in the case of frequent switching or braking – or 
if the speed is controlled continually below the rated speed. 
Forced ventilation (optional): Type of cooling IC 416 in accordance with EN / IEC 60034-6 
Cooling that does not depend on the speed is achieved by means of a unit that is 
independent of the motor operating state (forced ventilation). This unit is closed to the 
outside by a fan cover. It has its own main drive with fan impeller which creates the cooling 
air flow required for cooling the motor. 
 
Machines without a fan (optional) 
Cooling method IC 410
 
Surface cooling by free convection: Cooling method IC 410 according to EN / IEC 60034-6 
 
Surface cooling by relative movement of cooling air: Cooling method IC 418 according to 
EN / IEC 60034-6