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DSS tests in LEGNARO 22 nd to 25 th April 2008. A. BOUTY; S. BROUSSARD; A. LOTODE; Y. MARIETTE; Ch. VEYSSIERE: CEA/DSM/IRFU/SIS D. BAZZACCO: Univ. Padova E. FARNEA; A. GADEA; R. MENEGAZZO: LNL P. JONES: Univ. Jyväskylä T. ENGERT; T. HABERMANN; I. KOJOUHAROV: GSI
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DSS tests in LEGNARO 22nd to 25th April 2008 A. BOUTY; S. BROUSSARD; A. LOTODE;Y. MARIETTE; Ch. VEYSSIERE: CEA/DSM/IRFU/SIS D. BAZZACCO: Univ. Padova E. FARNEA; A. GADEA; R. MENEGAZZO: LNL P. JONES: Univ. Jyväskylä T. ENGERT; T. HABERMANN; I. KOJOUHAROV: GSI J. CACITTI; M. TRIPON: GANIL
Goal of these tests Realized with the detector S001 • To test the AXIS low voltage crate: • 48V • ±6V; ±12V for the preamps • 6.5V for the HV Box (Proto #1) • To test the HV box in an other environment (GSI (2006) -> LNL) • To Test the last version of the GUI developed by GSI
Means for the tests • Comparatives tests: • Patrice Medina 48V / AXIS • ±6V; ±12V NIM/ AXIS • 6.5V AXIS + HV Saclay/ Silena module Following analysis from Dino Bazzacco: PStestsWeek17-1.doc
Mechanical mounting of the LV crate EHG= 2.52 keV at 1332 keV ELG = 2.75 keV at 1332 keV Reference spectrum at high and low gain AXIS crate mounted (just grounded)
Mechanical mounting of the PLC PLC mounted (outside of the cabinet) and switched on EHG= 2.57 keV at 1332 keV ELG = 2.63 keV at 1332 keV Replacement of the 24V PS of the PLC by a linear floating PS; 6V and 12V AXIS on
Test of LV from AXIS (6V, 12V) versus NIM Final frequency spectra (100 k sample) before shutting down the HV Red: HG LV from Axis Green: HG LV from NIM bin Blue: LG LV from Axis Cyan: LG LV from NIM bin The spectra are very similar, with the ones using Axis slightly better at the lowest frequencies and those using NIM having lower amplitude in the peaks at 23 and 46 kHz.
Test of the 48V (1/2) With the Patrice 48V With the AXIS 48V
Test of the 48V (2/2) With the Patrice 48V Green and blue when adding a 400 and 600W resp. 48V AXIS with improvement on the grounding (copper braid shortened)
Using a GPBox (dual core preamp. inside) Red: 6, 12 and 48 V Axis Green: LV NIM, 48V Patrice
Comparison of AGATA and Silena HV • Using AXIS LV • Energy resolution (in keV) derived from INP
Noise spectra after 6 ms shaping trapezoidal shaping Red HV Silena (high gain signal) Green HV AGATA “” Blue HV Silena (low gain signal) Cyan HV AGATA “”
Integrated power spectra after ~6 ms trapezoidal shaper keV Red HV Silena (high gain signal) Green HV AGATA “” Blue HV Silena (low gain signal) Cyan HV AGATA “”
Problems to be solved: • Voltage regulators associated to long cables generate oscillations: regulators to be changed, • Temperature too high in the 48V module: • Geometry to be modified to improve the air path on the heat sink, • Vicor 600W PS to be tested. To check its influence on the signal, • Water cooling? • When profibus is reconnected, the crate stops briefly, • Safety of the 6 and 12V should not be linked with the 6.5V (when 6 and 12V stop, HV stops also), • 48V offset to be reduced, • Connectors (front panel Sub-D, 24V connectors, Profibus-DP)
Some problems can be avoided… • Reconnecting the PA when voltage is set induces an inrush current that trigs the safety of the 6 and 12V: not to be done… Removing the safety on the overcurrent might be dangerous in some cases. • July tests of revised AXIS box at Legnaro – on platform • Production Digitiser • Detector (Single detector ?) • Integration with rest of DSS ongoing