# Presentation: 394472

## Front End Equipment Protection System

- 3 Major Functions:
- Protect Front End components for damage from exposure to beam
- Insure components designed to control beam have sufficient cooling to operate without damage
- Insure components not designed to handle beam are not exposed to it
- Prevent propagation of vacuum loss
- Protect Storage Ring vacuum from catastrophic Beamline vacuum failures
- Segment Front End vacuum and limit effects of loss of vacuum
- Provide operator control of certain Front End components

## Devices requiring cooling

- Pre Mask or Mini Mask
- Found on newer ID at very beginning of front end
- Prevents the radiation from the AM bending magnet from entering the front end of the insertion device (ID) beamline
- Fixed Masks
- May be exposed to full beam power
- It contains and defines the beam
- Walls are cooled by water channels
- Older ones had copper porous media (mesh), newer have coils (much lower DP)
- Exit Mask
- A fixed mask located after the ratchet wall (sometimes just labeled as the next fixed mask)

## Devices requiring cooling

- Beam Position Monitors
- Multi-blade device providing beam position information
- Blade’s are CVC diamond coated to withstand temperatures to 1000o C
- Photon Shutters
- Must absorb full power of beam while closed
- BeWindows
- Not completely transparent to X-rays, so absorbs some power
- Provides vacuum isolation
- Filters
- Usually used with BeWindows to limit the spectrum the window must handle
- Usually cooled with another device so rarely called out.

## Devices unable to absorb beam

- Vacuum Valves
- Used to confine vacuum loss
- Must wait for beam to be removed before can be closed
- Safety Shutters
- Since sequencing is controlled by PSS, this can cause a problem when PSS closes the entire front-end together. It has already dumped the storage ring, so the SS’s are not in danger of exposure, but FEEPS has no way of detecting this.

## FEEPS’ control of the beam

- FEEPS has no direct control over any component capable of stopping the beam. It rely’s on permits to other systems to provide protection to the front-end components.
- FEEPS interfaces with:
- The Machine Protection System (MPS) to allow it to dump the storage ring. The interface to the MPS is though an additional box that contains some logic.
- Personnel Protection System to control PS1 and PS2.

## Typical Beam Protection Zones

- Requires FE-Shutter Permit to be removed and PS1 Close Request to provide protection

-  Components are protected relative to their position to the Photon Shutters

- Requires FE-Shutter Permit to be removed to provide protection

- Requires Ring Dump to provide protection

## Catastrophic Beamline Vacuum Failures

- Catastrophic Beamline vacuum failures are prevented by a separate but interregnal system of FEEPS. The Fast Closing System (also know as the VAT chassis) will independently close the Fast Valve and the Slow Valve on detection of a vacuum above a preset limit.
- The logic in the MPS chassis determines if it is necessary to dump the storage ring to protect the closing valves.  If PS1 is closed then the valve are already protected from the beam and a dump is not required.
- All of this takes place independent of the logic if the PLC. Its only part in this scenario is to provide PS1 position information.
- On the earlier versions only CC1 was used to determine if a vacuum event of such magnitude had occurred. On the newer versions the internal switch settings of the Fast Closing System have been chanced to require both CC1 and CC2 to agreed (anding logic) that a vacuum event of the required magnitude has occurred before closing the valves.

## Changes due to anding CC1 and CC2

- Unfortunately the change to the Fast Closing System can not be done without changes to other FEEPS’ subsystems.
- A different signal on the Fast Closing system must be monitored to determine if a trip has occurred.  This signal is of the opposite polarity as the originally monitored signal. This signal also goes to the MPS chassis and therefore its logic must also be changed.
- In earlier versions CC2 was used as an input to the PLC, as a trigger to close the Slow Valve for non-catastrophic vacuum events. CC2 is no longer available for this function as its set point has been changed to match that of CC1.
- Therefore the wiring, the PLC code and the MPS chassis logic must all be modified to implement this change to the Fast Closing System.

## Vacuum Segmentation

- The Front-End is basically divided into three vacuum segments. Only the Slow valve and the Front-End Exit Valve (FEV) are used to segment the Front-End.  The Fast Valve does not seal completely and is under the control of the Fast Closing System only. The Beamline Isolation Valve (BIV) is treated as additional protection from beamline vacuum loss and not a part of the segmentation.

- Beamline Vacuum

- Front-End Vacuum

- Storage Ring Vacuum

## Old Vacuum rules

- One ion pump per segment was monitored.
- If the ion pump in the Storage Ring segment detected loss of vacuum, the FE shutter permit was removed, the PS1 open request was removed, and once PS1 was detected as fully closed, the Slow Valve would close. At one time there was an additional signal from the controls group monitored.  Loss of this Storage Ring Vacuum Sensor signal would also cause the same response. This signal has been removed.
- If the ion pump in the Front-End segment detected loss of vacuum, the above would occur and the FEV would also be closed once PS2 was detected as fully closed.  Also a loss of vacuum detected by the CC2 would have the same effect.
- If the ion pump in the beamline segment detected a loss of vacuum, only the FE shutter permit would be removed and the FEV (and BIV if present) would close.  This same behavior would be triggered by a  loss of vacuum detected by the beamline vacuum sensor or the loss of the BLEEPS Vacuum permit.

## New Vacuum rules

- All ion pumps are monitored.
- Two adjacent ion pumps in a given segment must indicate a loss of vacuum to cause that section to be isolated.  The purpose is to reduce nuisance trips.  If the ion pumps on either side of a valve indicate loss of vacuum, that valve will be closed.  The idea being the leak is in one of the two sections and closing the valve will protect the other section.  The required permits are still removed and the valves do not close till the photon shutter protecting them is detected as fully closed.
- CC2 is no longer used in the vacuum segmentation logic.
- The beamline vacuum sensor should be anded with the last ion pump.
- No valve can be open unless all ion pumps in both segments it separates are showing good vacuum

## Most Common BM Configurations

- BMs 1,5,6,7,8,10,13,14,15,16,17,18,19,22,33,34
- BMs 2,9,12,20 (2 does not have a BIV)

- IP 1

- IP 2

- IP 3

- IP 4

- IP 5

- IP 6

- IP 7

- IP 8

- BL Vac. Sen.
- 16 & 22 only

- FM 1

- FM 2

- FM 3

- BPM 1

- BPM 2

- PS 1

- SV

- FV

- PS 2

- SS 1

- SS 2

- FEV

- BeWin

- IP 1

- IP 2

- IP 3

- IP 4

- IP 5

- IP 6

- IP 7

- IP 8

- FM 1

- FM 2

- FM 3

- BPM 1

- BPM 2

- PS 1

- SV

- FV

- PS 2

- SS 1

- SS 2

- FEV

- FM 4

- IP 9

- BIV

## Unique and New BM Configurations

- 35 BM
- BMs 11,21,23,24

- IP 1

- IP 5

- IP 6

- FM 1

- FM 3

- PS 1

- SV

- FV

- PS 2

- SS 1

- SS 2

- FEV

- BeWin

- IP 1

- IP 2

- IP 3

- IP 4

- IP 5

- IP 6

- IP 7

- FM 1

- FM 3

- BPM 1

- BPM 2

- PS 1

- SV

- FV

- PS 2

- SS 1

- SS 2

- FEV

- IP 8

- FM 2

- FM 2

- BeWin

## Most Common ID Configurations

- IDs 1,3,7,10,17,34, 35 (35 has BeWin instead of ComWin)
- IDs 2,5,6,8,9,12,13,15,18,19,20,33 (2 & 6 do not have a BIV)

- BPM 1

- FM 1

- IP 1

- PS 1

- SV

- FV

- BPM 2

- FM 2

- PS 2

- SS 1

- SS 2

- FEV

- IP 2

- IP 3

- IP 4

- IP 5

- IP 6

- ComWin

- BPM 1

- FM 1

- IP 1

- PS 1

- SV

- FV

- BPM 2

- FM 2

- PS 2

- SS 1

- SS 2

- FEV

- IP 2

- IP 3

- IP 4

- IP 5

- IP 6

- FM 3

- IP 7

- BIV

## Unique ID Configurations

- BPM 1

- FM 1

- IP 1

- PS 1

- SV

- FV

- BPM 2

- FM 2

- PS 2

- SS 1

- SS 2

- FEV

- IP 2

- IP 3

- IP 4

- IP 6

- IP 7

- BeWin

- BPM 1

- FM 1

- IP 1

- PS 1

- SV

- FV

- BPM 2

- FM 2

- PS 2

- SS 1

- SS 2

- FEV

- IP 2

- IP 3

- IP 4

- IP 6

- IP 7

- FM 3

- IP 5

- FILTER

- IP 5

- BeWin

- 11ID

- 14ID

## A Variation and Canted Undulator  ID Configurations

- IDs 4,16,22,31,32 (4 & 16 do not have BL Vac. Sen.)
- Canted Undulator: IDs 21,23,24

- BPM 1

- FM 1

- IP 1

- PS 1

- SV

- FV

- BPM 2

- FM 2

- PS 2

- SS 1

- SS 2

- FEV

- IP 2

- IP 3

- IP 5

- IP 6

- IP 7

- SV

- FV

- BPM 2

- PS 2

- SS 1

- SS 2

- FEV

- IP 3

- IP 4

- IP 5

- BeWin

- IP 4

- FM 3

- FM 4

- IP 8

- BIV

- BL Vac. Sen.

- MM

- Exit Mask

- IP 6

- BPM 1

- FM 1

- IP 1

- FM 2

- IP 2

- PreMask

- PS 1

- BL Vac. Sen.

- BIV

## New ID Configuration

- IDs 26,30

- SV

- FV

- BPM 2

- PS 2

- SS 1

- SS 2

- FEV

- IP 3

- IP 4

- IP 5

- BeWin

- Exit Mask

- IP 6

- BPM 1

- FM 1

- IP 1

- FM 2

- IP 2

- PreMask

- PS 1

- BL Vac. Sen.

- BIV

- FM 3

- FM 4