Shavkun V.
Candidate of Technical Sciences, Associate Professor of the Department of Electrical transport,
O.M. Beketov National University of Urban Economy in Kharkiv
Kharkiv, Ukraine
Мoroz M.
Candidate of Technical Sciences, Associate Professor of the Department of Occupational and Life Safety,
 O.M. Beketov National University of Urban Economy in Kharkiv
Kharkiv, Ukraine 

Abstract
The question of ensuring the appropriate level of electrical safety by controlling the technical condition of the insulation of traction motors is considered. Mathematical models of changing the parameters of electric machines and their resource on different routes of the corresponding trolleybus have been developed, which is confirmed experimentally, ie according to the operating data. The issues of the influence of the length of the haul on the temperature conditions of the power electrical equipment of trolleybuses, in particular traction electric motors, are considered.

 Keywords: trolleybus, electric motor, insulation, electrical safety, reliability, parameters, technical condition.    temperature conditions, loading factors, insulation.