58 DRIVES – MAINTAINING FREQUENCY INVERTERS
Without any maintenance, inverters will inevitably fail over time
due to the limited lifetime of electrolytic capacitors, which must be
periodically replaced. Failure modes, inspection and maintenance,
diagnostics and troubleshooting, as well as the general checks for
non-specialists: all are covered in this overview article
60 MOTORS – NEW EV MODELS GAIN TRACTION
Axial ux traction motors are already common in stationary
applications such as agricultural machinery and lifts; now, a number of
companies are now evolving the technology for automotive use, with
early-stage production commencing for use in electric vehicles. But
how do they work and what is their potential?
62 CONDITION MONITORING – DEPOT-BASED CM FOR RAIL
An o -line depot-based approach to condition monitoring uses
vibration measurements to assess the condition of the key assets
(traction motor, gearbox and axlebox) of passenger trains without
the need to remove equipment from the bogie. This is achieved by
rotating the wheelset on a depot wheel lathe. The ndings can be used
as the basis of a predictive maintenance strategy to improve eet
reliability and reduce part repair/overhaul costs
65 CONDITION MONITORING – VIBRATION
When vibration exceeds a certain threshold, it may be an indication
that the machine is deteriorating. Therefore, vibration is a useful tool
for investigating the status of rotating machinery, such as electric
motors, pumps and generators. Vibration analysis can locate a
potential problem and provide the opportunity for recti cation before
it causes further damage to the equipment
66 CORROSION – CHEMICAL PROTECTION
Cathodic protection is a way of controlling the electrochemical
process that causes corrosion, so that the part is not damaged. This
article explains the electrochemical process, how cathodic protection
prevents corrosion, and the applications of this approach
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