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Supported Circuits

1. RB - Main Dipole Circuit

source: Powering Procedure and Acceptance Criteria for the 13 kA Dipole Circuits, MP3 Procedure, https://edms.cern.ch/document/874713

Type Test Current Description Notebook Example report
HWC QH IST 0 Quench heater IST HWC_RB_QHDA HWC_RB_QHDA
HWC PIC2 I_MIN_OP Interlock tests with PC connected to the leads AN_RB_PIC2 AN_RB_PIC2
HWC PLI1.a2 I_INJECTION Current cycle to I_INJECTION AN_RB_PLI1.a2 AN_RB_PLI1.a2
HWC PLI1.b2 I_INJECTION Energy Extraction from QPS AN_RB_PLI1.b2 AN_RB_PLI1.b2
HWC PLI1.d2 I_INJECTION Unipolar Powering Failure AN_RB_PLI1.d2 AN_RB_PLI1.d2
HWC PLI2.s1 I_INTERM_1 Splice Mapping AN_RB_PLI2.s1 AN_RB_PLI2.s1
HWC PLI2.b2 I_INTERM_1 Energy Extraction from PIC during the ramp AN_RB_PLI2.b2 AN_RB_PLI2.b2
HWC PLI2.f1 I_INTERM_1 Quench heater provoked AN_RB_PLI2.f1 AN_RB_PLI2.f1
HWC PLIM.b2 I_SM_INT_4 Energy Extraction from QPS AN_RB_PLIM.b2 AN_RB_PLIM.b2
HWC PLIS.s2 I_SM Splice Mapping AN_RB_PLIS.s2 AN_RB_PLIS.s2
HWC PLI3.a5 I_INTERM_2 Current cycle to I_INTERM_2 AN_RB_PLI3.a5 AN_RB_PLI3.a5
HWC PLI3.d2 I_INTERM_2 Unipolar Powering Failure AN_RB_PLI3.d2 AN_RB_PLI3.d2
HWC PNO.b2 I_PNO+I_DELTA Energy Extraction from QPS AN_RB_PNO.b2 AN_RB_PNO.b2
HWC PNO.a6 I_PNO Energy Extraction from QPS AN_RB_PNO.a6 AN_RB_PNO.a6
Operation FPA I_PNO FPA during operation with magnets quenching AN_RB_FPA AN_RB_FPA

2. RQ - Main Quadrupole Circuit

source: Test Procedure and Acceptance Criteria for the 13 kA Quadrupole (RQD-RQF) Circuits, MP3 Procedure, https://edms.cern.ch/document/874714

Type Test Current Description Notebook Example report
HWC QH IST 0 Quench heater IST HWC_RQ_QHDA HWC_RQ_QHDA
HWC PIC2 I_MIN_OP Powering Interlock Controller AN_RQ_PIC2 AN_RQ_PIC2
HWC PLI1.b3 I_INJECTION Energy Extraction from QPS AN_RQ_PLI1.b3 AN_RQ_PLI1.b3
HWC PLI1.d2 I_INJECTION Unipolar Powering Failure AN_RQ_PLI1.d2 AN_RQ_PLI1.d2
HWC PLI2.s1 I_INTERM_1 Splice Mapping AN_RQ_PLI2.s1 AN_RQ_PLI2.s1
HWC PLI2.b3 I_INTERM_1 Energy Extraction from QPS AN_RQ_PLI2.b3 AN_RQ_PLI2.b3
HWC PLI2.f1 I_INTERM_1 Heater provoked quench AN_RQ_PLI2.f1 AN_RQ_PLI2.f1
HWC PLIM.b3 I_SM_INT_4 Energy Extraction from QPS AN_RQ_PLIM.b3 AN_RQ_PLIM.b3
HWC PLIS.s2 I_SM Splice Mapping at I_SM AN_RQ_PLIS.s2 AN_RQ_PLIS.s2
HWC PLI3.a5 I_SM, I_INTERM_2 Current cycle to I_INTERM_2 AN_RQ_PLI3.a5 AN_RQ_PLI3.a5
HWC PLI3.b3 I_INTERM_2 Energy Extraction from QPS AN_RQ_PLI3.b3 AN_RQ_PLI3.b3
HWC PNO.b3 I_PNO+I_DELTA Energy Extraction from QPS AN_RQ_PNO.b3 AN_RQ_PNO.b3
HWC PNO.a6 I_PNO Current cycle to I_PNO AN_RQ_PNO.a6 AN_RQ_PNO.a6
Operation FPA I_PNO FPA during operation with magnets quenching AN_RQ_FPA AN_RQ_FPA

3. IT - Inner Triplet Circuits

The main quadrupole magnet circuits of the 8 Inner Triplet (IT) systems in the LHC are composed of four single aperture quadrupole magnets in series and have a particular powering configuration, consisting of three nested power converters (PC), see Figure below.

Main quadrupole magnet circuit of the Inner Triplet system for IT’s at points 1 and 5 (left) and IT’s at points 2 and 8 (right).

Note that the configuration for the IT’s in points 1 and 5 is different from the configuration in points 2 and 8. An earth detection system is present at the minus of the RTQX2 converter. Detailed information concerning the converters is given in EDMS 1054483.

The two magnets Q1 and Q3 are type MQXA and the two combined magnets Q2a and Q2b are type MQXB. Q1 is located towards the interaction point.

Note that the IT’s at points 2 and 8 have a slightly higher nominal operating current than the IT’s at points 1 and 5, see Table 1.

Circuit I_PNO RQX I_PNO RTQX2 I_PNO RTQX1
RQX.L2, RQX.R2, RQX.L8, RQX.R8 7180 A 4780 A 550 A
RQX.L1, RQX.R1, RQX.L5, RQX.R5 6800 A 4600 A 550 A

Nominal operating currents for 7 TeV of the three PC’s as given in the LHC design report volume I. For the nominal current during HWC see EDMS 1375861.

source: Test Procedure and Acceptance Criteria for the Inner Triplet Circuits in the LHC, MP3 Procedure, https://edms.cern.ch/document/874886

Type Test Current Description Notebook Example report
HWC QH IST 0 Quench heater IST HWC_IT_QHDA HWC_IT_QHDA
HWC PCC.t4 ~ Power Converter Configuration part 2 AN_IT_PCC.t4 -
HWC PIC2 ~ Powering Interlock Controller check with standby current AN_IT_PIC2 AN_IT_PIC2
HWC PNO.d12 10% of I_PNO Powering Failure at +10% of nominal current AN_IT_PNO.D12 -
HWC PNO.d13 10% of I_PNO Powering Failure at -10% of nominal current AN_IT_PNO.D13 -
HWC PLI3.f6 I_PLI3 Heater Discharge Request at 2nd intermediate current (Note that I_RTQX1=0A AN_IT_PLI3.f6 AN_IT_PLI3.f6
HWC PNO.d14 50% of I_PNO Powering Failure at +50% of nominal current during a SPA AN_IT_PNO.d14 AN_IT_PNO.d14
HWC PNO.d15 50% of I_PNO Powering Failure at -50% of nominal current AN_IT_PNO.d15 AN_IT_PNO.d15
HWC PNO.a9 I_PNO+I_DELTA Training and plateau at nominal current AN_IT_PNO.a9 AN_IT_PNO.a9
HWC PNO.d16 90% of I_PNO Powering Failure at +90% of nominal current AN_IT_PNO.d16 AN_IT_PNO.d16
HWC PNO.d17 90% of I_PNO Powering Failure at -90% of nominal current AN_IT_PNO.d17 AN_IT_PNO.d17
Operation FPA I_PNO FPA during operation with magnets quenching AN_IT_FPA AN_IT_FPA

4. IPQ - Individually Powered 4-6 kA Quadrupole Circuits in the LHC Insertions

This section is a copy of a document created by Alexandre Erokhin (https://twiki.cern.ch/twiki/pub/MP3/Analysis_Manual_IPQ/MQM.pdf).

The Individually Powered Quadrupole magnets (IPQs) in the LHC are located on both sides of the Interaction Regions (IR), in the matching sector and in the dispersion suppressor. The IPQ circuits RQ4 to RQ7 are part of the matching sector, and the IPQ circuits RQ8 to RQ10 are part of the dispersion suppressor. The magnets Q4 to Q6 are operated at 4.5 K, whereas the magnets Q7 to Q10 are operated at 1.9 K.

Magnets in the Circuit Temperature Position General information
2MQM 1.9 K RQ7.L4, RQ7.R4 I Nominal: 5390A, I_Ultimate: 6820A
L tot: 2x15 mH, L per aperture: 15 mH
max(di/dt): 12.917 A/s
2x2MQM 1.9\4.5* K RQ7.L1, RQ7.R1 RQ7.L2, RQ7.R2 RQ7.L5, RQ7.R5 RQ7.L8, RQ7.R8 RQ5.L8*, RQ5.R2* I Nominal: 5390A\4310A*, I_Ultimate: 5820A\4650A*
L tot: 2x2x15 mH, L per aperture: 15 mH
max(di/dt): 12.917 A/s
2MQML 1.9\4.5* K RQ5.L1*, RQ5.R1* RQ5.L5*, RQ5.R5* RQ6.L1*, RQ6.R1* RQ6.L5*, RQ6.R5* RQ8.L1, RQ8.R1 RQ8.L2, RQ8.R2 RQ8.L4, RQ8.R4 RQ8.L5, RQ8.R5 RQ8.L6, RQ8.R6 RQ8.L8, RQ8.R8 RQ10.L1, RQ10.R1 RQ10.L2, RQ10.R2 RQ10.L4, RQ10.R4 RQ10.L5, RQ10.R5 RQ10.L6, RQ10.R6 RQ10.L8, RQ10.R8 I Nominal: 5390A 4310A*, I_Ultimate: 5820A 4650A*
L tot: 2x21 mH, L per aperture: 21 mH
max(di/dt): 12.917 A/s
2MQMC 1.9 K\4.5K* Does not exist as an individual power circuit (exists only in combination with 2MQM) I Nominal: 5390A\4310A*, I_Ultimate: 5820A\4650A*
L tot: 2x11 mH, L per aperture: 11 mH
max(di/dt): 12.917 A/s
2MQM+2MQML 4.5 K RQ6.L2, RQ6.R2 RQ6.L8, RQ6.R8 I Nominal: 4310A, I_Ultimate: 4650A
L tot: 2x15 mH + 2x21 mH
max(di/dt): 12.917 A/s
2MQM+2MQMC 1.9 K RQ9.L1, RQ9.R1 RQ9.L2, RQ9.R2 RQ9.L4, RQ9.R4 RQ9.L5, RQ9.R5 RQ9.L6, RQ9.R6 RQ9.L8, RQ9.R8 I Nominal: 5390A, I_Ultimate: 5820A
L tot: 2x15 mH + 2x21 mH
max(di/dt): 12.917 A/s

The MQM quadrupole consists of two individually powered apertures assembled in a common yoke structure. Depending on a subsector there are few kinds of power circuits:

  • 2MQM

    Apertures B1 of 2 magnets are powered in series with one power supply Apertures B2 of 2 magnets are powered in series with second power supply. The return bus is common for both power circuits.

  • 2x2MQM

    Apertures B1 of 4 magnets are powered in series with one power supply Apertures B2 of 4 magnets are powered in series with second power supply. The return bus is common for both power circuits.

  • 2MQML – long version

    Apertures B1 of 2 magnets are powered in series with one power supply Apertures B2 of 2 magnets are powered in series with second power supply. The return bus is common for both power circuits.

  • 2MQM + 2MQML

    Apertures B1 of 2 MQM and 2 MQML are powered in series with one power supply Apertures B2 of 2 MQM and 2 MQML are powered in series with second power supply. The return bus is common for both power circuits.

  • 2MQM + 2MQMC

    Apertures B1 of 2 MQM and 2 MQMC are powered in series with one power supply Apertures B2 of 2 MQM and 2 MQMC are powered in series with second power supply. The return bus is common for both power circuits.

Another subclass of IPQ magnets are MQYs. This section is a copy of a document created by Alexandre Erokhin (https://twiki.cern.ch/twiki/pub/MP3/General_Info_IPQ/MQY.pdf).

Magnets in the Circuit Temperature Position General information
2x2MQY 4.5 K RQ4.L2, RQ5.L2 RQ4.R2, RQ4.L8, RQ4.R8, RQ5.R8 I Nominal: 3610A, I_Ultimate: 3900A
L tot: 2x2x74 mH, L per aperture: 74 mH
max(di/dt): 10.8 A/s
2MQY 4.5 K RQ4.L1, RQ4.R1, RQ4.L2, RQ5.L2 RQ4.R2, RQ5.L4, RQ6.L4 RQ5.R4, RQ6.R4 RQ4.L5, RQ4.R5, RQ4.L6, RQ5.L6 RQ4.R6, RQ5.R6 I Nominal: 3610A, I_Ultimate: 3900A
L tot: 2x74 mH, L per aperture: 74 mH
max(di/dt): 10.8 A/s

The MQY wide-aperture quadrupole consists of two individually powered apertures assembled in a common yoke structure. Depending from a Subsector there are two kinds of power circuits:

  • 2MQY*

    Apertures B1 of 2 magnets are powered in series with one power supply. Apertures B2 of 2 magnets are powered in series with second power supply. The return bus is common for both power circuits.

    Note: * in accordance with layout database 2 MQY means apertures B1 and B2 of the one magnet MQY type.

  • 2x2MQY

    Apertures B1 of 4 magnets are powered in series with one power supply. Apertures B2 of 4 magnets are powered in series with second power supply. The return bus is common for both power circuits.

Quench Detector Type

DQQDC – current leads quench detector

DQAMG – controller attached to global protection

Current Leads: - Typical resistance for U_RES: 7 uOhm - Threshold for U_HTS: 3 mV, 1 s - Polarity convention: if I_B1 = I_B2 > 0, LD1:U_RES < 0, LD3:U_RES > 0 - PM file: - Buffer range: 0 to 250, event at point 50 - Time range: -10 to 40 s - Frequency: 5 Hz (dt = 200 ms)

Magnet: - See polarity convention here above - U_RES_B1 = U_1_B1 + U_2_B1 - U_RES_B2 = U_1_B2 + U_2_B2 - Threshold on U_RES: 100 mV, 10 ms - Attention: B1 signals & B2 signals can be shifted by 4ms from each other - If pure inductive signal: - If dI/dt < 0: - U_1_Qx = Ldi / dt < 0 - U_2_Qx = -Ldi / dt > 0 - PM file: - Buffer range: 501 to 1500, event at point 1000 - Time range: -2 to 2s - Frequency: 250Hz (dt = 4ms)

The protection of the MQM quadrupole during a quench is assured by eight strip quench heaters placed on the outer layer of each coil octant. For redundancy, the heaters are connected in two circuits, such that each circuit covers all four poles and powered by independent power supplies.

The protection of the MQY quadrupole during a quench is assured by sixteen strip quench heaters of two different widths. Eight wide quench heaters are mounted between the second and third layers and the narrow heaters on the outer surface of the fourth layer.

This number of heaters is required to limit the voltage during quench in case of failure of some of the heaters. Both the inner and outer heaters are connected in two circuits, each circuit covering all four poles and powered by independent power supplies.

Type Test Current Description Notebook Example report
HWC QH IST 0 Quench heater IST HWC_IPQ_QHDA HWC_IPQ_QHDA
HWC PCC.3 I_PCC Power Converter Configuration - -
HWC PIC2 I_MIN_OP Powering Interlock Controller check with standby current in the circuits. AN_IPQ_PIC2 AN_IPQ_PIC2
HWC PLI1.c3 I_INJECTION Fast Power Abort at injection current. AN_IPQ_PLI1.c3 AN_IPQ_PLI1.c3
HWC PLI2.f3 I_INTERM_1 Unbalanced ramp and Quench Heater Firing AN_IPQ_PLI2.f3 AN_IPQ_PLI2.f3
HWC PLI2.e3 I_INTERM_1 Unbalanced slow power abort AN_IPQ_PLI2.e3 AN_IPQ_PLI2.e3
HWC PNO.f4 I_PNO Symmetric Ramp and Symmetric Quench Heater Firing - -
HWC PNO.a7 I_PNO+I_DELTA Powering to I_PNO + I_DELTA and unbalanced SPA AN_IPQ_PNO.a7 AN_IPQ_PNO.a7
HWC PNO.c4 I_PNO Current Lead test and FPA from I_PNO AN_IPQ_PNO.c4 AN_IPQ_PNO.c4
Operation FPA I_PNO FPA during operation with magnets quenching AN_IPQ_FPA AN_IPQ_FPA

source: Test Procedure and Acceptance Criteria for the Individually Powered 4-6 kA Quadrupole-Circuits in the LHC Insertions, MP3 Procedure, https://edms.cern.ch/document/874884

5. IPD - Beam Separation Dipoles D1-D4

This section is a copy of a document created by Alexandre Erokhin https://twiki.cern.ch/twiki/pub/MP3/General_Info_IPD/separation_dipole.pdf

Magnets in the Circuit Temperature Position General information
MBX (D1) 1.9 K RD1.L2, RD1.R2, RD1.L8, RD1.R8 I Nominal: 5800A, I_Ultimate: 6100A
L tot: 26 mH, L per aperture: 26 mH
max(di/dt): 17.453 A/s
MBRC (D2) 4.5 K RD2.L1, RD2.R1, RD2.L5, RD2.R5 I Nominal: 4400A, I_Ultimate: 4670A
RD2.L2, RD2.R2, RD2.L8, RD2.R8 I Nominal: 6000A, I_Ultimate: 6500A
L tot: 52 mH, L per aperture: 26 mH
max(di/dt): 18.147 A/s
MBRS (D3) 4.5 K RD3.L4, RD3.R4 I Nominal: 5520A, I_Ultimate: 6000A
L tot: 26 mH, L per aperture: 26 mH
max(di/dt): 18.147 A/s
MBRB (D4) 4.5 K RD4.L4, RD4.R4 I Nominal: 5520A, I_Ultimate: 6000A
L tot: 26 mH, L per aperture: 26 mH
max(di/dt): 18.147 A/s

Superconducting beam separation dipoles of four different types are required in the Experimental Insertions (IR 1, 2, 5 and 8) and the RF insertion (IR 4). Single aperture dipoles D1 (MBX) and twin aperture dipoles D2 (MBRC) are utilized in the Experimental Insertions. They bring the two beams of the LHC into collision at four separate points then separate the beams again beyond the collision point. In the RF Insertions two types of twin aperture dipoles, each type with two different aperture spacings are used: D3 (MBRS) and D4 (MBRB). The D3 and D4 magnets increase the separation of the beams in IR 4 from the nominal spacing 194 mm to 420 mm. D2 and D4 are the twin apertures magnets with common iron core for both apertures. D3 is a twin apertures magnet with independent iron cores for each aperture.

The MBRC dipole consists of two individually powered apertures assembled in a common yoke structure.

  • MBX – D1

    Single aperture of the magnet powered with one power supply.

  • MBRC – D2

  • MBRB – D4

    Apertures B1 and B2 of the magnet are powered in series with one power supply.

  • MBRS - D3

    Apertures B1 and B2 of the magnet are powered in series with one power supply but series connection done in the DFBA.

Quench Detector Type
DQQDC - current leads quench detector
DQAMG - controller attached to global protection

Current Leads: - Typical resistance for U_RES: 7 uOhm - Threshold for U_HTS: 3 mV, 1s - Polarity convention: Arrows show how signals are measured. If I > 0, LD1: U_RES > 0, LD2: U_RES < 0 - PM file - Buffer range 0 to 250, event at point 50 - Time range: -10 to 40 s - Frequency: 5 Hz (dt = 200 ms)

Magnet: - See polarity convention in the circuit schematics - U_RES_B1 = U_1_B1 + U_2_B1 - Threshold on U_RES_B1: 100 mV, 10 ms - U_RES_B2, U_1_B2, U_2_B2 and U_INDUCT_B2 are given for diagnostics only - Signals are measured with -2.5 V offset and with the gain factor = 0.0012 - Attention: B1 signals and B2 signals can be shifted by 4 ms from each other - If pure inductive signal and di/dt < 0: - U_1_B1 = L di/dt < 0 - U_2_B1 = -L di/dt < 0

  • PM file
  • Buffer range 501 to 1500, event at point 1000
  • Time range: -2 to 2 s
  • Frequency: 250 Hz (dt = 4 ms)
Type Test Current Description Notebook Example report
HWC QH IST 0 Quench heater IST HWC_IPD_QHDA HWC_IPD_QHDA
HWC PCC.3 I_PCC Power Converter Configuration 1Q: Calibration of the PC - -
HWC PIC2 I_MIN_OP Powering Interlock Controller check with standby current in the circuits. AN_IPD_PIC2 AN_IPD_PIC2
HWC PLI1.c2 I_INJECTION Fast Power Abort at injection current. AN_IPD_PLI1.c2 AN_IPD_PLI1.c2
HWC PLI2.f2 I_INTERM_1 Heater Provoked Quench AN_IPD_PLI2.f2 AN_IPD_PLI2.f2
HWC PLI3.c5 I_INTERM_3 Measurement of splice resistance and Fast Power Abort at intermediate current AN_IPD_PLI3.c5 AN_IPD_PLI3.c5
HWC PNO.a8 I_PNO+I_DELTA Powering to I_PNO + I_DELTA AN_IPD_PNO.a8 AN_IPD_PNO.a8
HWC PNO.c6 I_PNO Fast Power Abort at Nominal Current and Lead Test AN_IPD_PNO.c6 AN_IPD_PNO.c6
Operation FPA I_PNO FPA during operation with magnets quenching AN_IPD_FPA AN_IPD_FPA

source: Test Procedure and Acceptance Criteria for the Separation Dipoles Circuits, MP3 Procedure, https://edms.cern.ch/document/874885

6. 600A Circuits

The 600-A circuits come in one of two main variants:

  • circuits with
  • and without EE.

Each variant may or may not be equipped with a DC contactor ensuring the effectiveness of the crowbar in case of a PC short circuit. Moreover, the magnets of several circuits are equipped with parallel resistors, in order to decouple the current decay in a quenching magnet from that in the rest of the circuit. Figure below shows a generic circuit diagram, equipped with EE and parallel resistor, as well as lead resistances and a quench resistance.

source: Test Procedure and Acceptance Criteria for the 600 A Circuits, MP3 Procedure, https://edms.cern.ch/document/874716

Table below provides a list of circuits to be used with these analysis notebooks

RCBX family RCD/O family Remaining 600A circuits with EE Remaining 600A circuits without EE
RCBXH1 RCD RCS RQS (RQS.L)
RCBXH2 RCO RSS RQSX3
RCBXH3 ROD RQT12
RCBXV1 ROF RQT13
RCBXV2 RQTL9 RQTL7
RCBXV3 RQS (RQS.A) RQTL8
RQTD RQTL10
RQTF RQTL11
RSD1
RSD2
RSF1
RSF2
RU

Another useful resource to find out which 600 A circuits belong to which category is the circuit tree on the MP3 website http://cern.ch/mp3

Type Test Current Description Notebook Example report
Operation FPA I_PNO FPA during operation with magnets quenching AN_600A_with_without_EE_FPA AN_600A_with_without_EE_FPA
Operation FPA I_PNO FPA during operation with magnets quenching AN_600A_RCDO_FPA AN_600A_RCDO_FPA
Operation FPA I_PNO FPA during operation with magnets quenching AN_600A_RCBXHV_FPA AN_600A_RCBXHV_FPA

7. 80-120A Circuits

Figure below shows the electrical diagram of the 80-120 A corrector circuits including the connection to the PC. It’s important to note the positioning of the crowbar with respect to the DCCTs. During a power abort the current will transfer from the PC into the crowbar and the measured current (I_MEAS) goes immediately to almost 0 A, and is therefore not representative for the current in the cold part of the circuit including the magnet. Note that there is no QPS present in these circuits but that the PC will shut-down in case of overvoltage.

Type Test Current Description Notebook Example report
Operation FPA I_PNO FPA during operation with magnets quenching AN_80-120A_FPA AN_80-120A_FPA

8. 60A Circuits

The LHC comprises a total of 376 pairs of horizontal and vertical orbit correctors which are installed at each focusing and defocusing main quadrupole magnet in the arcs. Quenches on 60 A magnets are detected by the power converter through magnet impedance growing. In addition, the power converter also provides current lead protection. The Figure below shows the circuit diagram of the 60 A arc orbit correctors.

Type Test Current Description Notebook Example report
Operation FPA I_PNO FPA during operation with magnets quenching AN_60A_FPA AN_60A_FPA