Abstract: In order to obtain a better production capacity.It is necessary to arrange the maintenance and trouble shooting of AC variable frequency speed regulation system reasonably under the background of the openpit Mine largescale equipment such as electric shovels,roller drills gradually use the AC frequency conversion speed regulation system.In the aspect of trouble shooting of frequency conversion device,most of the troubles can be solved by analyzing the common troubles and making corresponding measures.In the other aspect of frequency conversion equipment maintenance,according to the characteristics of large temperature difference and dust concentration in operating environment,the maintenance work of dust removal and ventilation and heat dissipation is scientifically instituted.The periodic maintenance and common trouble removal of frequency converter in openpit mining improve the efficiency of frequency converter in openpit mining,and stable guarantee the production and operation of mining.

Key words: Open pit mining, Frequency control, Troubleshooting, Maintenance, Dust removal, Ventilation for heat dissipation