"- We consider standard analysis scenarios, i.e., all signals can be queried. Depending on what signal is missing, an analysis can raise a warning and continue or an error and abort the analysis.\n",
"- In case an analyzed signal can't be queried, a particular analysis is skipped. In other words, all signals have to be available in order to perform an analysis.\n",
"- It is recommended to execute each cell one after another. However, since the signals are queried prior to an analysis, any order of execution is allowed. In case an analysis cell is aborted, the following ones may not be executed (e.g. I\\_MEAS not present). \n",
"\n",
"# Plot Convention\n",
...
...
@@ -42,53 +41,35 @@
},
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"text": [
"Analysis executed with lhcsmapi version: 1.3.323\n",
"Analysis executed with lhc-sm-hwc notebooks version: 1.1.0\n"
"|i_a_rcbx_df\t|DataFrame\t|A\t|PM|I_A is the raw RCBX power converter current logged around the FPA with high sampling frequency|\n",
"|i_meas_rcbx_df\t|DataFrame\t|A\t|PM|I_MEAS RCBX power converter current is filtered I_A with lower sampling frequency and longer duration|\n",
"|i_ref_rcbx_df\t|DataFrame\t|A\t|PM|The reference current of an RCBX power converter, I_REF|\n",
"|events_action_rcbx_df\t|DataFrame\t|text\t|PM|event action storing information about the state of an RCBX PC operation, e.g. FAULT, EVENTS.ACTION|\n",
"|events_symbol_rcbx_df\t|DataFrame\t|text\t|PM|event action storing information about source of an RCBX PC FPA, e.g. TRG EXTERNAL FAST ABORT, EVENTS.SYMBOL|\n",
"\n",
"Note that **rcbx** in the table above denotes RCBXH and RCBXV, i.e., there are four signals for each circuit.\n",
"\n",
"*ANALYSIS*:\n",
"- determination of the source of an FPA trigger based on EVENTS.SYMBOL and EVENTS.ACTION signals\n",
"- detection of the start of a quench as a deviation of I_A and I_REF\n",
"|i_meas_nxcals_rcbx_df |DataFrame |A |NXCALS|Power converter current in an RCBX circuit, I_MEAS|\n",
"|u_res_nxcals_rcbx_df\t|DataFrame\t|V\t|NXCALS|Resistive voltage of magnets measured with QPS in an RCBX circuit, U_RES|\n",
"|u_res_rc_df\t|DataFrame\t|V\t|PM|Resistive voltage of magnets measured with QPS in an RCBX circuit, U_RES|\n",
"\n",
"Note that **rcbx** in the table above denotes RCBXH and RCBXV, i.e., there are two signals for each circuit.\n",
"\n",
"*ANALYSIS*:\n",
"- Check if the U_RES signal before a quench is increasing for at least one board, which would indicate a QPS trip\n",
"- Calculate the initial voltage slope of U_RES signal. The slope is calculated as a ratio of the voltage change from 50 to 200 mV and the corresponding time change.\n",
"|i_dcct_rcbx_df\t|DataFrame\t|A\t|PM|DC current leads of QPS in an RCBX circuit, I_DCCT|\n",
"|i_didt_rcbx_df\t|DataFrame\t|A/s\t|PM|di/dt current leads of QPS in an RCBX circuit, I_DIDT|\n",
"|u_diff_rcbx_df\t|DataFrame\t|V\t|PM|differential voltage of QPS in an RCBX circuit, U_DIFF|\n",
"|u_res_rcbx_df\t|DataFrame\t|V\t|PM|resistive voltage (after inductance compensation) of QPS in an RCBX circuit used for quench detection, U_RES|\n",
"\n",
"Note that **rcbx** in the table above denotes RCBXH and RCBXV, i.e., there are two signals for each circuit.\n",
"\n",
"*ANALYSIS*\n",
"- Check the integrity of all four signals (U_DIFF, I_DCCT, I_DIDT and U_RES). If one of the signals (especially U_DIFF or I_DCCT) stays at zero or shows wrong values the cabling of this quench detector could have issues. Compare U_DIFF (measured signal) to U_REF (signal compensated for inductive voltage).\n",
source: Test Procedure and Acceptance Criteria for the 600 A Circuits, MP3 Procedure, <ahref="https://edms.cern.ch/document/874716/5.3">https://edms.cern.ch/document/874716/5.3</a>
%% Cell type:markdown id: tags:
# Analysis Assumptions
- We consider standard analysis scenarios, i.e., all signals can be queried. Depending on what signal is missing, an analysis can raise a warning and continue or an error and abort the analysis.
- In case an analyzed signal can't be queried, a particular analysis is skipped. In other words, all signals have to be available in order to perform an analysis.
- It is recommended to execute each cell one after another. However, since the signals are queried prior to an analysis, any order of execution is allowed. In case an analysis cell is aborted, the following ones may not be executed (e.g. I\_MEAS not present).
# Plot Convention
- Scales are labeled with signal name followed by a comma and a unit in the square bracket, e.g., I_MEAS, [A]
- If a reference signal is present, it is represented with a dashed line
- If the main current is present, its axis is on the left. Remaining signals are attached to the axis on the right. The legend of these signals is located on the lower left and upper right, respectively.
- The grid comes from the left axis
- Title contains timestamp, circuit name, signal name allowing for re-access the signal.
- The plots assigned to the left scale got colors: blue (C0) and orange (C1). Plots presented on the right have colors red (C2) and green (C3).
- Each plot has an individual time-synchronization mentioned explicitly in the description.
- If an axis has a single signal, change color of the label to match the signal's color. Otherwise, the label color is black.
Analysis executed with lhc-sm-hwc notebooks version: 1.1.0
%% Cell type:markdown id: tags:
# 1. Select FGC Post Mortem Entry
%% Cell type:markdown id: tags:skip_cell
In order to perform the analysis of a FPA in an RCD/O 600A circuit please:
1. Select circuit name (e.g., RC.A12B1)
2. Choose start and end time
3. Choose analysis mode (Automatic by default)
Once these inputs are provided, click 'Find FGC PM entries' button. This will trigger a search of the PM database in order to provide a list of timestamps of FGC events associated with the selected circuit name for the provided period of time. Select one timestamp from the 'FGC PM Entries' list to be processed by the following cells.
**Note that 24 hours is the maximum duration of a single PM query for an event. To avoid delays in querying events, please restrict your query duration as much as possible.**
The analysis for MP3 consists of checking the existence of PM file and of consistency of the PM timestamps (PC, QPS). The criterion of passing this test described in detail in 600APIC2.
In short the following criteria should be checked:
- 2 PM DQAMGNA (A+B) files and 1 PM EE file should be generated for 600 A circuits with EE
- Difference between QPS board A and B timestamp = 1 ms
- PC timestamp is QPS timestamp +/- 20 ms
If one or more of these conditions are not fulfilled, then an in-depth analysis has to be performed by the QPS team.
|i_a_rcbx_df |DataFrame |A |PM|I_A is the raw RCBX power converter current logged around the FPA with high sampling frequency|
|i_meas_rcbx_df |DataFrame |A |PM|I_MEAS RCBX power converter current is filtered I_A with lower sampling frequency and longer duration|
|i_ref_rcbx_df |DataFrame |A |PM|The reference current of an RCBX power converter, I_REF|
|events_action_rcbx_df |DataFrame |text |PM|event action storing information about the state of an RCBX PC operation, e.g. FAULT, EVENTS.ACTION|
|events_symbol_rcbx_df |DataFrame |text |PM|event action storing information about source of an RCBX PC FPA, e.g. TRG EXTERNAL FAST ABORT, EVENTS.SYMBOL|
Note that **rcbx** in the table above denotes RCBXH and RCBXV, i.e., there are four signals for each circuit.
*ANALYSIS*:
- determination of the source of an FPA trigger based on EVENTS.SYMBOL and EVENTS.ACTION signals
- detection of the start of a quench as a deviation of I_A and I_REF
- calculation of the MIITs
- calculation of the quench current
- calculation of the duration of a plateau / the ramp rate before a quench (based on PM event buffer)
*GRAPHS*:
- dashed blue line denotes the start of a quench (I_A starts to deviate from I_REF)
analysis_rcbxv.calculate_max_i_earth_pc(i_earth_rcbxv_df,col_name='Earth Current V')
```
%% Cell type:markdown id: tags:
# 5. QDS
The quench voltage U_RES is calculated according to the following formula:
\begin{equation}
U_{\text{RES}} = U_{\text{DIFF}} + L d/dt (I+U_{\text{DIFF}}/R).
\end{equation}
Note that I_DCCT is the QPS signal name, even though the current is actually measured not with a DCCT, but with a LEM detector, hence the poorer quality w.r.t. to the FGC I_A/B/MEAS signals that are measured with a DCCT.
It can be seen from the sign convention in the figure below that a resistive voltage always has opposite sign to the measured current.
As U_DIFF contributes directly to U_RES, the resolution of U_RES is, at least partially, limited by that of U_DIFF. Moreover, U_RES is affected by the noisy time derivative of the current signal.
The QPS signals that are communicated to the post-mortem system have only 12 bit resolution.
## 5.1. Resistive Voltage
*QUERY*:
|Variable Name |Variable Type |Variable Unit |Database|Comment
|i_meas_nxcals_rcbx_df |DataFrame |A |NXCALS|Power converter current in an RCBX circuit, I_MEAS|
|u_res_nxcals_rcbx_df |DataFrame |V |NXCALS|Resistive voltage of magnets measured with QPS in an RCBX circuit, U_RES|
|u_res_rc_df |DataFrame |V |PM|Resistive voltage of magnets measured with QPS in an RCBX circuit, U_RES|
Note that **rcbx** in the table above denotes RCBXH and RCBXV, i.e., there are two signals for each circuit.
*ANALYSIS*:
- Check if the U_RES signal before a quench is increasing for at least one board, which would indicate a QPS trip
- Calculate the initial voltage slope of U_RES signal. The slope is calculated as a ratio of the voltage change from 50 to 200 mV and the corresponding time change.
*GRAPHS*:
First plot (U_RES and I_MEAS prior to a quench)
- t = 0 s corresponds to the FGC timestamp
Second plot (U_RES and the initial slope of U_RES)
|i_dcct_rcbx_df |DataFrame |A |PM|DC current leads of QPS in an RCBX circuit, I_DCCT|
|i_didt_rcbx_df |DataFrame |A/s |PM|di/dt current leads of QPS in an RCBX circuit, I_DIDT|
|u_diff_rcbx_df |DataFrame |V |PM|differential voltage of QPS in an RCBX circuit, U_DIFF|
|u_res_rcbx_df |DataFrame |V |PM|resistive voltage (after inductance compensation) of QPS in an RCBX circuit used for quench detection, U_RES|
Note that **rcbx** in the table above denotes RCBXH and RCBXV, i.e., there are two signals for each circuit.
*ANALYSIS*
- Check the integrity of all four signals (U_DIFF, I_DCCT, I_DIDT and U_RES). If one of the signals (especially U_DIFF or I_DCCT) stays at zero or shows wrong values the cabling of this quench detector could have issues. Compare U_DIFF (measured signal) to U_REF (signal compensated for inductive voltage).
*CRITERIA*
-**U_RES < 0.7*100 mV and noise of U_RES on the plateaus < 20mV**
