Hello Jacob,

In India the usual practice is to use LT motor up to 160 kW or 180 kW and HT motors for more than 160 kW or 180 kW. These are not rigid boundaries, and one can also find LT motors for somewhat higher kW. I am sure aforesaid practice will be generally in line with the international practice.

There could be varies reasons such as availability of motors, motor size (weight), power supply cable size, voltage drop, implication on size / price on MCC, transformer, etc.

Electrical engineers or motor manufacturers can describe specific reason for such practice. Such practice has certainly come as concurrence from many agencies i.e. electrical designers, manufacturers, users etc.

Regards,

Ishwar G Mulani.

Author of Book : Engineering Science and Application Design for Belt Conveyors.

Advisor / Consultant for Bulk Material Handling System & Issues.

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 25882916 ■

Hello Jacob,

I suggest you to refer to the reputed manufacturers of induction motors in your country. You will be readily able to get the leaflet from them, which will specify the necessary information such as voltage, frequency, kW, speed, frame size, dimensions etc. You will find that the product shifts from LT to HT at certain range. This provides the indication about the prevailing practice in your country.

Coming to your suggestion to know about the specific standard, a very famous international company in India mentions that their LT motors conform to:

Performance: as per IS 325, IEC 34, Part 1

Dimensions according to IS 1231, IEC 72

I am not electrical engineer, so I will not like to dwell further about the specific number of the standard. Also, there are numerous standards like DIN, BS, ISO, JIS, American and so on.

Regards,

Ishwar G Mulani.

Author of Book : Engineering Science and Application Design for Belt Conveyors.

Advisor / Consultant for Bulk Material Handling System & Issues.

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 25882916 ■