PRI Completes Frequency Conversion System for Metro-North

West Babylon, NY – PRI’s Automation & Controls engineers have successfully commissioned a frequency conversion system for a mobile substation as part of Metro-North Railroad’s Mobile Signal Power Substation Contract.

PRI’s scope for this project included providing a 60Hz to 100Hz frequency conversion motor alternator set as well as an associated PLC control system for Metro-North’s mobile substation. The control system includes one 60Hz switchgear control section, one MA control cabinet section with associated mimic bus and breaker control switches, and one 100Hz switchgear control section.

The control cabinets utilize a redundant PLC system, which eliminates a single point of equipment failure. The PLC system is also responsible for starting and stopping the motor, and monitors associated alarms and analog signals gathered from three protective relays.

All monitoring and controls are accessed either locally within the mobile substation via the use of an HMI or remotely. All signals required for operating the motor are accessed using the DNP3 communication protocol. This allows an operator in a remote control center to start and stop the motor and monitor all alarms associated with the frequency conversion system.