What does microprocessor control for a locomotive mean?
‘Microprocessor control’ can mean a few different things. A few of the newer electric locomotive models such as the WAP-5 or WAG-9 with complex 3-phase AC drives have circuitry and equipment controlled by microprocessors. In these, the microprocessor or computerized control is an integral part of the locomotives’ design. Some of the newer diesel locos such as the WDG-4, WDP-4, WDM-3D, etc., also use a fair bit of microprocessor control for their onboard systems. These advanced locomotives can be truly described as being computer-controlled or microprocessor-controlled. However, the term ‘microprocessor control’ is also widely applied to certain models of WAP-4 and other locos that have been retrofitted with a monitoring system that uses computerized circuitry to replace some of the electromechanical relays and switches that were part of the original design of these locos. Systems monitored by the microprocessor circuits include the DJ, silicon rectifier, battery chargers, etc. The adva
