PHW, based in Pittsburgh, Penn., is a leading manufacturer of cab signaling systems and other fail-safe electronic train control systems for the North American railroad and mass transit industries. PHW's onboard system is used on the North East Corridor by Amtrak and associated railroads as part of Amtrak's ACSES PTC system. ACSES is the first PTC system to be approved for operation by the Federal Railroad Administration under the requirements of the Rail Safety Improvement Act of 2008. Cab signaling systems make train operations more efficient, allow higher operating speeds and improve system safety. According to Invensys, the PHW PTC products will be a major expansion of Invensys Rail's North American PTC product line.