Among the key components to be installed in this new facility are equipment power supply units and redundancy balance modules, the reliability of which will determine the facility’s ability to meet demanding experimentation programmes.
European XFEL's ‘X-Ray Optics & Beam Transport’ team will be responsible for the transportation and manipulation of the X-ray beams. This happens in a 900m long section of the tunnel, where the X-rays are guided via tubes in which a vacuum of 10-6 mbar must be maintained.
All the necessary ancillary equipment, such as valves, sliders, motors for positioning mirrors, and various monitoring systems, are fully automated, and these critical control systems demand a high level of reliability from their power supplies.
The power supply units chosen for this project were provided by Murrelektronik GmbH, based in Oppenweiler, Germany. As well as the various control systems installed along the X-ray guidance section, Murrelektronik Emparro power supply units also provide the necessary 24V supply to a number of other critical components at the facility.
According to European XFEL engineer, Timo Korsch, the selection of Emparro power supplies was influenced by a number of factors. Firstly, as the equipment cabinets are only 1.2m high, access is somewhat restricted, so a simple connection method was deemed necessary. Emparro units feature spring clamp terminations, designed for simple push-in wiring without need for tools. The contacts, once made, are permanent and never need retightening.
Secondly, thanks to an efficiency rating of up to 95 percent, Emparro power supplies run cooler. "Less heat dissipation means less cooling is required in the air-conditioned control cabinets, which saves energy and reduces our costs", Mr Korsch adds.
When the European XFEL facility is fully operational, researchers from all over the world will use it to conduct their experiments. Because of this, the operators are very keen to see the facility working without interruption in order to maximise the amount of time available for research and experimentation.
Access to the tunnel is restricted by the control system while the facility is operating, so it can only be entered for troubleshooting during scheduled maintenance times.
As a result, the power supply is designed with redundancy. Two power supply units are each operated with different phases. They are decoupled by a MB Redundancy Balance module that ensures equal loads on both power supply units. This prolongs the life of the units significantly and, if one of the power supplies should fail, operations can continue until the next scheduled maintenance day.
Both the Emparro and the MB Redundancy Balance units feature signal contacts; this is an additional benefit for the facility’s maintenance team as it provides the possibility of remote diagnostics. In the event of a voltage drop, for example, the condition can be signalled directly to the duty maintenance operative.
In addition to their ease of connection and high efficiency, Emparro power supplies are capable of providing a 50 percent power boost for up to four seconds as well as offering a long mains failure bridging time. The units are metal-housed for optimum EMC performance and no de-rating is necessary from -25 to +60°C.