P. Timmer Nikhef Amsterdam Afd. ET. Acceptance test 400V – 12V DC-DC converter Chroma DC Electronic load Delta Elektronika SM 400-AR-4 400V 2A 800W GPIB PC with Windows 7 and labview 2013 Current Measurement HP34401A or Agilent Filter DUT: 400V->12V DC-DC converter Plus 400V Gnd 12V Plus 12V gnd 400V Plus 400V Gnd 400V GPIB USB Ethernet Voltage Measurement HP34401A or Agilent GPIB to USB GPIB to USB Contact: Techniek: Paul Timmer Org: Ruud Kluit De getekende “onderdelen” zijn beschikbaar en kunnen per direct worden gebruikt.

P. Timmer Nikhef Amsterdam Afd. ET. DC-DC converter in the KM3Net project For the KM3Net project, situated at the bottom of the Mediterranean Sea, 100 km from shore, power is needed to supply the sensitive detector systems. The Km3net detector is supplied with a voltage of 10000V. In a container at the bottom of the sea this voltage is converted to 400V. The container with these converter has several 400V outputs. One output supplies a so called detector unit. A detector unit consist of 18 glass spheres witch houses 31 Photon multipliers. These spheres are situated with a mutual distance of 25 meter on a string. The first sphere is situated 200 meters above the sea bottom. A detector unit can be placed hundreds of meters from the converter that supplies the 400V. The total length of the cable will cause a voltage drop of +/- 30V at the top of the detection unit. When the 400 – 12V DC-DC converter switches on automatically, the voltage of the 400V cable will drop. The DC-DC converter will switch on at 350 V and has a hysteresis of 30V (switches off at 320V). When the converter is switched on 12 V will occur at the output. The supply remains in regulation with an input voltage between 321V and 400V. The minimum power of the DC-DC converter at 321V is 10 Watts. Acceptance test 400V – 12V DC-DC converter

P. Timmer Nikhef Amsterdam Afd. ET. Acceptance test 400V – 12V DC-DC converter Specifications of DC-DC converter Converter switches on at 350 V. Converter switches of at 320 V. Nominal input voltage is 360V. Converter is in regulation between 321 and 400V. Output of the converter is 12 V. Maximum output power is 16 W. (output power depends on the input voltage). When overload or a short occurs the output switches off. For switching on again the input voltage has to go down tot zero first. Ripple at output is 200mV

P. Timmer Nikhef Amsterdam Afd. ET. Acceptance test 400V – 12V DC-DC converter What to test. After every measurement, store the data. Start with filling in the number of the converter: OM_400V_DCDC_v5.3 nr…… Check if the number is already used, if so, ask to test again. After filling in the number the test can start. Show on the monitor what the program is testing. Load is switched of. 1: Ramp up the input voltage (slowly when 345 V is reached, 2 volts per second.) and check if the output voltage appears when input voltage is 350 V. (348 V 352 V) 2: Measure the output voltage at 360 V. (11,6 V 12,6 V) 3: Ramp down the input voltage and check at what input voltage the output voltage switches off. (around 320 V, 318 V 322 V) 4: Switch on electronic load at 10 Watt and repeat step 1,2 and 3. (Electronic load adjusted to medium power.) 5: Adjust input voltage to 360 V, switch on the load, start with a load of 8 W, ramp up the load with 0,5 Watt steps and check at what output power the converter switches of. 6: Switch converter off ( wait until input voltage is zero and wait 4 seconds) and on (input voltage > 350V) and adjust input voltage to 325 V. (no load) 7: Measure input current, output voltage, output current and output power. Calculate the efficiency of the converter. 8: Increase the electronic load with 1 Watt. 9: Repeat step 7. 10: Repeat step 7 every time after a load increase of 1 Watt until a load is reached of 11 Watt. 11: Adjust load to 0 Watt. Increase the input voltage with 5V. 12: Repeat step 7 – 11 13: Stop when last measurements are done at 400V. 14: Save all data in EXEL files with the date and time of the test