topDesign & Operation Responsibles

Yves THUREL Yves THUREL Project leader
Michel GEORGES Michel GEORGES Tests, Qualification


CERN uses commercial units as well as home-made/designed power sources, mainly when commercial & off-the shelves solution doesn't correspond to CERN specific uses. This service check the compatibility of commercial units with regards to CERN requirements.


TE-EPC organize a dedicated service to validate commercial power sources in order to evaluate they can be suitable for given applications.

Power Unit Technical Evaluation Flowchart .xmind

More info in this FAQ below:
What to expect from such internal service? How much time for a final report? Can i access result data? How is decided if a relevant commercial unit can be of interest or not? Power Supply of interest: Voltage or Current Source?


Range of interest is defined below, reflecting the maximum coupling decoupling devices capability (voltage & current):
Input range Output range
voltage current voltage current
[1; 3] Phases
[0; 400] VAC
< 63 A [0; 200] VDC [0; 1000] ADC



These technical points are part of a standard process to evaluate a commercial power source:
Type Description Comment Standards / ref. Guide
Electrical Performances Evaluation
EMC-Emissions Conducted Noise According to IEC-61204-3
but also regarding internal limits, checked on both input and output sides, requiring specific apparatus.
EMC-Immunity Burst Tests
(7 ns / 50 ns)
According to
IEC 61000-4-4
Surge Tests
(1.2 μs / 50 μs)
According to
IEC 61000-4-5
General Performances Efficiency, Output Ripple, Voltage and current (if the case) Bandwidth...
Input Line Variations AC phase loss, Over-Voltage variations, Inrush current...
Output Load Variations Dynamic Response to sudden (0..100%, 50..100%) load variation.
Interfaces Evaluation
Analogue & Digital
Interfaces Digital signals: a review of signals available, the protocole, communication bus, and their compatibility with existing CERN systems. Analog signals: test of the integrity of these signals to evaluate if they should be directly used, to (Imonitor, Vmonitor, etc...)
Control Integration
using FGC controller
Controllability Power source is controlled by a CERN FGC controller, with the addition of DCCTs, and performances are checked as a current source, in the current range [0.1; 100] % of nominal output current.
Mechanical Integration
Mechanical A short document, with the analyse of internal construction, repairability, weight, fan location. Focus is put on a possible realization in a standard Power Rack.
Suitability Integration
Suitability A short document, with a review of components choices: fuses, breaker (, fans, magnetics, but also a quick survey of the standards completion.
Documentation Review
Documentation All documentation is gathered, and quickly evaluated.