MODBUS/TCP controller for the power supplies in als BTS beam line

The development, testing and commissioning of a self- contained power supply controller for four 100 KW power supplies for the upgraded Booster to Storage Ring (BTS) beam line at the Advanced Light Source( ALS) at the Lawrence Berkeley Laboratory, is presented. The power supply controller is a 3U high, rack-mount chassis that contains the regulation control-loop amplifiers, 16-bit DAC with microcontroller and a micro PLC (Programmable Logic Controller) for power-supply state- machine control. Local control is achieved via pushbuttons and a color LCD touch screen. Remote control is mediated via micro PLC using embedded Modbus/TCP. Using a unique, data logging system, the operational parameters of the regulation loop can be safely monitored and recorded while the system is running at full power. The entire design is based on optimum reliability, safety and ease of troubleshooting and repair. A modular design for key control components, allows the power supply to operate in a nominal mode, even if one or two ancillary internal modules fail. This allows for continued beam operation until it is convenient to service the unit, keeping beam availability as high as possible.