1. 13.02.2008MPP Meeting Sandor Feher Inner Triplet Powering Should include the IR quads and the DFBX especially the power leads. DFBX commissioning doc was completed long time ago. IT Powering document is ready for review; practically follows the same logic as all of the other circuits. Picked to discuss issues relevant to HWC: Polarity of the Triplet Expected QPS (MPP) signals Firing Heaters due to Interlock (covered by H. Thiesen)

2. 13.02.2008MPP Meeting Sandor Feher KEK supplied CERN supplied MQXA MQXB MQXA MCBXAMCBXA MQSXMQSX MCBXMCBX MCBXMCBX BPMBPM BPMBPM LMQXC LMQXB LMQXA LQXC LQXB LQXA To IP  “Q3” “Q2” “Q1” C/WC/W TASTAS pipes pipes* beam tube FNAL supplied IK 1 IK 3 IK 2 IK 4 MCSOXMCSOX Inner Triplet As a unit it has never been tested => famous pressure test “failure” Individually cold tested all the magnets however interconnects are done at CERN concern should be with: Cryogenics – new control for the Power leads – 600A leads require flow rate control Powering – Coupled PC

3. 13.02.2008MPP Meeting Sandor Feher MQXB Quadrupoles

4. 13.02.2008MPP Meeting Sandor Feher MQXB Quadrupoles Data collected in 2005

5. 13.02.2008MPP Meeting Sandor Feher MQXA Quadrupoles

6. 13.02.2008MPP Meeting Sandor Feher MQXA Quadrupoles

7. 13.02.2008MPP Meeting Sandor Feher IR layout & polarities F/D/FD/F/D F/D/F D/F/D F/D/F D/F/DF/D/F Q3/Q2/Q1Q1/Q2/Q3 Polarity of 2&8 and 1&5 are the same

8. 13.02.2008MPP Meeting Sandor Feher Left LD3 LD1 LD2 LD4 Right LD1 LD3 LD4 LD2 Reiner LD1 LD2 LD3 LD4 + - + + -- This configuration polarity is valid for 1&5 and it is reversed for 2&8 DFBX DFBX lead label number is increasing from the IP IP 1234(56)

9. 13.02.2008MPP Meeting Sandor Feher QPS circuits RQX RTQX Nice summary document for basic info useful for powering written by A. Erokhin; Can be found in the CCC

10. 13.02.2008MPP Meeting Sandor Feher After a quench has been detected all of the quench heaters will be fired. Lead Voltage will change polarity Example of a full energy deposition test: Q2 at 12 kA Q1 (Q3) at 7kA (lead between Q1 – Q2 at IP1)

11. 13.02.2008MPP Meeting Sandor Feher Q2 and Q1(Q3) magnet Half Coil Voltages Maximum Voltages are within ± 50V

12. 13.02.2008MPP Meeting Sandor Feher Q2 Heater signal measured on the Heater itself To check the actual heater discharge curves total (cold heater + cable) resistances have to be measured prior to fire the heaters M1 = 11.4 & 11.5 Ω M2 = 10.7 & 10.5 Ω Magnet Hi-pot = 1200v @ 2uA Heater Hi- Pot = 1400v @ 0.04uA

13. 13.02.2008MPP Meeting Sandor Feher Heaters are fragile due to the heater wire specified by CERN We have to reduce the number of heater firing as much as possible

14. 13.02.2008MPP Meeting Sandor Feher Hello Sandor, Here is a table with the required information: IR L-side R-side 1 D/F/D F/D/F 2 F/D/F D/F/D 5 D/F/D F/D/F 8 F/D/F D/F/D F -> horizontally focusing quadrupole, i.e. the force pushes in the h- plane a positively charge particle rotating in the clock-wise direction (Beam 1) towards the centre of the magnet. D -> horizontally defocusing quadrupole, i.e. the force pushes in the h-plane a positively charge particle rotating in the clock-wise direction (Beam 1) away from the centre of the magnet. The sequence of three letters stand for Q1/Q2/Q3 I hope this helps. Do not hesitate to contact me in case of questions. Cheers Massimo

15. 13.02.2008MPP Meeting Sandor Feher Information on LHC IRQ Polarity R. Bossert, M. Lamm 1-17-08

16. 13.02.2008MPP Meeting Sandor Feher Direction of current shown by red arrows. Figure 1. MQXB Coil Schematic Every magnet has two leads, one designated “A” and one designated “B”. A schematic for the MQXB (used in Q2 cold mass) is shown in Figure 1. There is no schematic available for the Q1 or Q3 cold masses. A B

17. 13.02.2008MPP Meeting Sandor Feher Figure 2. Figure 3. Isometric of end B lead from Quadrant 4 Q4 inner lead “B” Q3 inner lead “A” A lead from Quadrant 3. For the MQXB, the A lead is the Quadrant 3 inner coil lead and the B lead is the Quadrant 4 inner coil lead, coming out of the magnet as shown in Figure 2 (looking into lead end) Q2 consists of two MQXBs postioned back to back. As the leads come out of the Q2 and enter the interconnection region, the A lead is on the top and the B lead is on the bottom, as shown in Figure 2.

18. 13.02.2008MPP Meeting Sandor Feher X Leads L3 and L4 come out here in this direction Figure 4. A lead from Quadrant 3. B lead from Quadrant 4 X X Current into paper Current out of paper If the MQXB is powered so that the current flow is into the A” lead and out of the “B” lead, the field direction is as shown in Figure 4 (Verified by M. Lamm and J. DiMarco in October 2003). This field direction is designated the “forward” direction.

19. 13.02.2008MPP Meeting Sandor Feher B lead splice, the one on top MQXA to bus splice MQXA (used for both Q1 and Q3 leads) exit the lead end of the magnet as shown in Figure 5. Q1 is configured exactly as shown. Q3 is rotated 180 degrees, but the busses are arranged so that the B lead is still on top when the leads enter the interconnection area. A lead splice, the one underneath Figure 5

20. 13.02.2008MPP Meeting Sandor Feher For the MQXA in Q1, the lead end of the magnet is facing away from the IP, and configured as shown in Figure 6. “+” and “-” on right and left leads are from Akira Yamamoto April 2000. When looking into the lead end, the lead on the right, labeled “+” is called “A” and the lead on the left, labeled “-” is called “B” as shown. When current flows into A and out of B lead it produces a field as shown designated “forward”. (Verified by M. Lamm and J. DiMarco in October 2003) Figure 6 Lead end of Q1 + - A B A lead B lead When the leads enter the interconnection area, for the MQXA in Q1, the B lead is on top and the A lead is on the bottom. Q1 Lead Configuration

21. 13.02.2008MPP Meeting Sandor Feher When current flows into A and out of the B lead it produces a field as shown designated “forward”. (Verified by M. Lamm and J. DiMarco in October 2003) When the leads enter the interconnection area, for the Q3, the B lead is on top and the A lead is on the bottom. Q3 Lead Configuration 10mm x 50mm bus slot up Figure 7 Lead end of Q3 + - A B A lead B lead For the MQXA in Q3, the lead end of the magnet is facing toward from the IP, and configured is as shown in Figure 7. “+” and “-” on left and right leads are from Akira Yamamoto April 2000. When looking into the lead end, the lead on the left, labeled “+” is called “A” and the lead on the right, labeled “-” is called “B” as shown.

22. 13.02.2008MPP Meeting Sandor Feher An electrical schematic of the triplet is shown in Figure 8. A and B leads are connected as shown, with current direction defined by the black arrows. As noted previously, A leads are on top for Q2, and B leads are on top for Q1 and Q3. “Forward focus” is defined as the focus from a magnet powered from A to B and placed in the “forward” direction, i.e., with the lead end facing the IP. So for each individual element: IP Q1: Powered from A to B, lead end facing IP, therefore “forward focus”. Q2a: Powered from A to B, lead end facing away from IP, therefore “backward focus”. Q2b: Powered from B to A, lead end facing IP, therefore “backward focus”. Q3: Powered from B to A, lead end facing away from IP, therefore “forward focus”. Figure 8. Conclusion