Open AccessDesign, ignition risk assessment and testing of increased safety high tension induction motor for explosive atmospheres
Author(s) -
Ahirwal Bhagirath,
Chatterjee Tarun Kumar
Publication year - 2013
Publication title -
iet electric power applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.815
H-Index - 97
eISSN - 1751-8679
pISSN - 1751-8660
DOI - 10.1049/iet-epa.2012.0337
Subject(s) - rotor (electric) , automotive engineering , ignition system , engineering , mechanical engineering , aerospace engineering
Increased safety (Exe) motors are widely used in zone 1 and 2 areas. Exe high tension (HT) motor is designed in such a way that it cannot produce any arc/spark and temperature of any part of motor in normal operating condition and specified abnormal condition. The risk assessment of Exe HT motor was introduced in the year of 2008 by ET22 Committee of Bureau of Indian Standards in IS:6381‐2004 standards in India. The Exe motors were designed and risk assessment of ignition was carried out as per new standards. All necessary test on the Exe HT designed motors are also described in this paper. The starting time or blocking time in normal or abnormal condition of Exe motor depends on the insulation system of motor. Time t E of rotor or stator winding depends on some design parameters like mass of rotor winding, rotor copper loss, starting torque etc. Time t E is very critical for any HT Exe motor and it should not be less than 5 s as per IS:6381‐2004 and IS/IEC 60079‐7:2006. The Exe motors mentioned in this paper have been manufactured by Bharat Heavy Electricals Ltd. (BHEL), Bhopal, India during the project and main author was project leader.