1. We are specialized in the production of Motorized transfer trolleys of our own brands, our rail Motorized transfer trolley have KPD, KPDS, KPDZ, KPC, KPJ, KPX, KPT and KP series according to the different electricity supply mode. Different working environment need different specification, power supply and operation ways. 2. Working Principle: KPD series is a 36V power supply low voltage rail motorized transfer trolley, It is equipped with Slippery Touch Line Power Supply System, Single phase AC 380V is steped-down to a single phase 36V safe voltage with Step down transformer. AC 380V is transformed into AC 36V by way of transformer into rails, and then sent to the current rectifier on the platform truck, which supply 36V direct current to DC motor.