SLIDE 1
RHIC BEAM PERMIT SYSTEM
(Power Supply Interlock)
RHIC Beam Permit System:
- Concentrates beam permit signals
- Beam position monitors
- Loss monitors
- Cryogenics
- Super conducting magnet quench detectors
- Have dual function
- Beam permit system input
- Power supply interlock input
- Allows beam entry into RHIC ring
- Allows continued beam presence in RHIC ring
Three Permit System Rings:
- Permit ring (driven by permit & quench inputs)
- Blue power supply interlock ring (driven by blue quench inputs)
- Yellow power supply interlock ring (driven by yellow quench inputs)
- A ring consists of permit system modules connected by:
- Fiberoptic cable for distances greater than 25 Meters
- Twisted pair copper short distances
- A ring carries
- 10Mhz carrier: GOOD = CARRIER
Any Ring Carrier Failure = Beam Dump
- Permit ring
- Beam dump
- Blue power supply interlock ring
- Beam dump & blue power supply crowbar
- Yellow power supply interlock not affected
- Yellow power supply interlock ring
- Beam dump & yellow power supply crowbar
- Blue power supply interlock not affected
SLIDE 2
ACCELERATOR CONTROLS GROUP
V120 Beam Permit System Module
V120 Beam Permit Module contains:
- 8 FAIL SAFE Inputs
- Support systems drive a 50 Ohm load to TTL level
- Module input optoisolated
- 6 Permit inputs (beam position monitor, etc.)
- 2 Quench inputs (magnet quench detectors)
- 3 FAIL SAFE outputs
- Capable of driving a 50 Ohm load to TTL level
- Beam permit level
- Blue power supply interlock
- Yellow power supply interlock
- 3 FAIL SAFE carriers (input/output)
- Permit ring
- Blue power supply interlock ring
- Yellow power supply interlock ring
- RHIC event link input
- Input transformer isolated
- Missing carrier detector (fail safe)
- Master V120 module additional input/output
- Blue & yellow index inputs
- Optoisolated
- Missing pulse detector (fail safe)
- DISABLED FOR SEXTANT TESTS
- 2 FAIL SAFE outputs
- Capable of driving a 50 Ohm load to TTL level
- Blue & yellow beam dump outputs
- Synchronized to beam indices
- SYNCHRONIZATION DISABLED FOR SEXTANT TESTS
- DUMP IS IMMEDIATE ON FAILURE DETECTION
- Abort event trigger
FAIL SAFE means - any input signal loss is a failure
- Failure detected by a support system
- Most support system failures
- Cable failure
SLIDE 3
V120 Beam Permit System Module
RHIC Control System Module
- V120 module is a 6U x 4HP VME module
- Supported by:
- T120 Transition module
- T120 User input/output strip
- Master V120 Module
- Master module determined by:
- Position (10 o'clock house)
- Jumper patch
- Has connection to beam dump system
- Has connection to RHIC event link
- Will accept a software beam dump
- Master/Slave Modules Contain:
- 16 bit status register w/interrupt on change-of-state
- Permit/quench status
- Ring carrier status
- RHIC event link status
- Master/slave module indicator
- Permit input control register
- Disable permit inputs (unused inputs)
- Not effective on quench inputs
- Jumper patch disables quench inputs
- 8 permit mask registers
- Mask control via RHIC event link
- Not effective on quench inputs
- 9 32 bit time stamp registers
- Time stamp counter
- 1 MHz clock
- Reset by RHIC event link event code
- Time stamp 8 permit/quench input failures
- Not effected by masks
- Time stamp permit system upstream carrier failure
SLIDE 4
V120 Beam Permit System Module
Permit/Quench Input Failures
Permit/Quench Inputs:
- All failures latched
- A failure is signal loss > 2 usec
- Time of failure registered
- Status register change-of-state interrupt
- As a permit input latches - if unmasked
- Downstream permit carrier terminated
- Beam permit level terminated
- Status register change-of-state interrupt
- As a permit input latches - if masked
- Status register change-of-state interrupt
- As the blue quench input latches
- Downstream permit carrier terminated
- Beam permit level terminated
- Downstream blue interlock carrier terminated
- Yellow power supply system not effected
- Blue interlock level terminated
- Yellow power supply system not effected
- As the yellow quench input latches
- Downstream permit carrier terminated
- Beam permit level terminated
- Downstream yellow interlock carrier terminated
- Blue power supply system not effected
- Blue interlock level terminated
- Blue power supply system not effected
Permit/Quench Input Latch Reset
- Latch doesn't reset as input is restored
- Reset following a VMEbus time stamp register read
- Reset following event code
- RPR (reset permit registers)
- RQR (reset quench registers)
- IMPORTANT
- LATCHED MASKED PERMIT INPUTS MUST BE RESET
BEFORE THE MASK TERMINATES!!!!!
- IF NOT, BEAM DUMP AS MASK TERMINATES!!!!
SLIDE 5
V120 Beam Permit System Module
Initialization
Power Supply Initialization
- Done before permit initialization
Check all V120 Modules Quench Input Status
If OK
- Software triggers a RQR event code
- Master V120 module initiates both interlock carriers
- Slave V120 modules receive & retransmit interlock carriers
- Master and slave enable local power supply interlocks
- All modules delay RQR approximately 0.5 sec
- After 0.5 seconds master V120 module:
- If upstream carrier detected, carrier transmission continues
- If not detected, appropriate carrier transmitter disabled
- appropriate power supply interlock terminated
- After 0.5 seconds slave V120 modules:
- If upstream carrier detected, retransmit carrier
- If not detected, appropriate power supply interlock terminated
Permit System Initialization
- Done after power supply initialization
Check all V120 Modules Permit Input Status
If OK
- Software triggers a RPR event code
- Master V120 module initiates permit carrier
- Slave V120 modules receive & retransmit permit carrier
- All modules delay RPR approximately 0.5 sec
- After 0.5 seconds master module:
- If upstream carrier detected, carrier transmitter enabled
- If not detected, carrier transmitter disabled
- Initiates a beam dump
- Local beam permit level terminated
- After 0.5 seconds slave modules:
- If upstream carrier detected, retransmit carrier
- If not detected, local beam permit level terminated
SLIDE 6
V120 Beam Permit System Module
Carrier Propagation
Initial Carrier Circle of RHIC Ring (Permit or Interlock Carriers)
- Requires 240 to 320 msec
- Fiberoptic receivers detect carrier
- Each require approximately 8 msec to unblank
- 30 to 40 in full system
Subsequent Carrier Circles of RHIC Ring (Permit or Interlock Carriers)
- Requires 18 to 20 usec
Permit or Interlock Fault Carrier Fail Propagation
- Requires 2 us/V120 module
- Approximately 80 to 100 usec (worst case) to dump