1. Status of the retriggering boxes and measurements
J. Rodziewicz

2. Overview
JURA3 measurements - noise coupled to the RTL from PTC when the generator is pulsing;
JURA3 measurements – signals delivered to the PTC from the RTB for the pickup presence check;
JURA3 measurements of the chassis potential ‘jump’ with reference to the copper base of the generator;
JURA1 – MKDH pickups source signals at min and max energy;
RTB output transformer saturation - test to be performed in the tunnel;
Status of the RTBs;
11/18/2019
Document reference

3. Noises coupled to the RTL from the PTC MKD pulsing at 450GeV
PTC mesurements connected
PTC mesurements disconnected
RTL is high impedance, voltage is probed though the output transformer of the RTB by the oscilloscope (CH1);
Measurement in configuration no ‘PTC meas.’ repeated at 2TeV and 4TeV,coupled noise was negligible; Repeated with the MKB RTB Proto;
It has been observed that the PTC measurement outputs are coupling the noises into the RTL. In this measurements an old PTC was used.
Is it critical? Noise level to be confirmed with the new PTC…
CH1 – RTL voltage x1.2 ; CH2 – TRIGGERS IN
11/18/2019
Document reference

4. New RTB outputs to the PTC Summary table
For the test purpose we use a dummy PTC.
The PTC outputs are loaded with 3.6kΩ
PRINA is the CTs2 signal received by the PTC
CPDIS is the VRD signal received by the PTC
RTB input stage schematics
Amp (PRINA) [V]
Amp (CPDIS) [V]
450 GeV
CTs2 & VRD 29
CTs2 only
2 (noise)
VRD only 32
7 TeV 56 49
20 (noise)
14 (noise) 48
At the first view the observed coupling is favorable for the RTS function as it generates signal to the RTL from the pulsing generator.
In principal the noise level measured at high energy is lower than the signal level at low energy. Therefore it is possible to set a fixed threshold in the PTC for the detection of a faulty pickup.
SAM is deactivated during the pulse sequence of the generators.
Example waveform. Signal at the RTL (CH1) and delivered by a PTC output (CH2).
-> All RTB inputs are disconnected
-> Generator is pulsing at 7.5 TeV

5. Chassis potential ‘jump’
The MKD generator is pulsing at 7.5TeV. New measurement was done with reference to the cooper base of the generator.
Previous measurement
New measurement
Peak to peak 23V
New measurement shows 23Vp-p Vs. 11.3Vp-p measured previously with reference to the bottom of the chassis.
11/18/2019
Document reference

6. MKDH | CTs2 450GeV
Consolidated generator (JURA 1 measurements done on 05/07/2019)
Trigger (Time ‘0’) is set to 2V threshold of the ‘TRIGGERS IN’ signal available at the generator front panel;
11/18/2019
Document reference

7. MKDH | VRD 450GeV
Consolidated generator (JURA 1 measurements done on 05/07/2019)
Trigger (Time ‘0’) is set to 2V threshold of the ‘TRIGGERS IN’ signal available at the generator front panel;
11/18/2019
Document reference

8. MKDH | CTs2 7TeV
Consolidated generator (JURA 1 measurements done on 05/07/2019)
Trigger (Time ‘0’) is set to 2V threshold of the ‘TRIGGERS IN’ signal available at the generator front panel;
11/18/2019
Document reference

9. MKDH | VRD 7TeV
Consolidated generator (JURA 1 measurements done on 05/07/2019)
Trigger (Time ‘0’) is set to 2V threshold of the ‘TRIGGERS IN’ signal available at the generator front panel;
11/18/2019
Document reference

10. MKD RTB output transformer saturation considerations –> September Test
INPUT Transformers
Allowable flux:
80 uV.s
First diagnostic pulses (issued by Trigger Delay) will be propagated within ~110us following the main pulse of consolidated LBDS.
In order to correctly propagate the diagnostic pulses the RTL impedance should be close to the nominal. It is mandatory to ensure that the flux seen by the output transformers along the line will be below the limit given by the manufacturer.
OUTPUT Transformers
Allowable flux:
280 uV.s
Simplified simulation gives sufficient margin, however in real system apart of the propagation delay the phases differences between generators can lead to the saturation of the output transformers.
Therefore the RTL test at high energy will be highly recommended in the tunnel before the MKD RTB production launch.
11/18/2019
Document reference

11. MKB RTB status EDA-04023-V1-0 Pre-series box validated in JURA1
Production ready to be launched, but few improvements will be possibly applied to the PCBs (routing, labeling etc.)
11/18/2019
Document reference

12. MKD RTB status EDA-04101-V1-0 PCB design released
Mechanics to be prototyped
3 Prototype units pending
Number of Pre-series for the test in the tunnel to be confirmed
11/18/2019
Document reference

13. Summary
A unwanted coupling from the pulsing generator to the measurement link between RTB and PTC was observed. So far it is not hazardous for any of the sub-systems. MKD chassis potential voltage ‘jump’ of the pulsing generator was measured almost twice higher when referenced to the generator ‘copper base’ instead of the chassis ‘bottom’ The signals from the pickups of consolidated MKBH generator are updated and can be used for further analysis. MKD transformers matching to be confirmed in the tunnel (date to be confirmed). MKB Pre-series validated in JURA1. MKD box in prototyping.
11/18/2019
Document reference