Proposed Element Naming Convention for CBETA

All element names will use 8 characters All characters will be upper case.

Format: *TSSCCCNN*_signal_name


T = Technical System

SS = Sector or Sub-system

CCC = Component Type (must be unique in L0, no overloading)

NN = Instance Number within Sector or Subsystem

Signal_name = See the signal naming convention above

Currently defined Technical Systems are:

C Cryogenics

V Vacuum


M Magnets

I Instrumetation

P Personnel

E Equipment

K Controls

Y Cryomodule (ICM)

L Laser/Optics

G Gun

U Utilities

"Z" Main LINAC Cryomodule (MLC)

Currently defined Sectors and Sub-systems are:


A1 Gun to Cryomodule

A2 Cryomodule

A3 Cryomodule to Fork

B1 Merger Branch to MLC

B2 Merger Branch to Diagnostic Line

C1 Straight Branch from Diagnostic Line

C2 Bend Branch from Diagnostic Line

D1 MLC Through first dipole steering toward dump

D2 Remainder of dump line

S1 - S4 Splitter lines

R1 - R4 Recombiner lines

FA FFA Return Loop First Arc

TA FFA Return Loop First Transition

ZA FFA Return Loop First Half of Straight

ZM FFA Return Loop Middle of Straight

ZB FFA Return Loop Second Half of Straight

TB FFA Return Loop Second Transition

FB FFA Return Loop Second Arc


5K 5K Helium system

BL Beam Line

CP Cathode Prep System

F1 RF Power and Control Elements for Cavity 1

F2 RF Power and Control Elements for Cavity 2

F3 RF Power and Control Elements for Cavity 3

F4 RF Power and Control Elements for Cavity 4

F5 RF Power and Control Elements for Cavity 5

FB RF Power and Control Elements for Buncher Cavity

FD RF Power and Control Elements for Deflecting Cavity

FG RF General Power and Control Elements

FX RF Transmission related (heliax, etc.)

HX Heat Exchanger

VB Valve Box

PU Pump Skid

TC HTC Test Cryomodule

R1 Cavity 1 (Cryomodule Section)

R2 Cavity 2 (Cryomodule Section)

R3 Cavity 3 (Cryomodule Section)

R4 Cavity 4 (Cryomodule Section)

R5 Cavity 5 (Cryomodule Section)

P0-9 Coupler 0-9 (Cryomodule Section)

RT Test Cavity (HTC Cryomodule Section)

H1 HOM 1 (Cryomodule Section)

H2 HOM 2 (Cryomodule Section)

H3 HOM 3 (Cryomodule Section)

H4 HOM 4 (Cryomodule Section)

H5 HOM 5 (Cryomodule Section)

HE HOM East (HTC Cryomodule Section)

HW HOM West (HTC Cryomodule Section)

GE Gun End (Cryomodule Section)

DE Dump End (Cryomodule Section)

PS Protection System

DC Device Ready Chain

L0 L0 Global

LR Laser Room Global

LA Laser Room Annex

TO Laser Transport Optics

GT Gun Laser Table

CR Control Room Global

UT Utilities

MG Magnet Global

W3 Wilson 3rd Floor Compressors

Currently defined Component Types:


DPA Dipole, Type A Dipole
CHA Corrector, Type A, Horizontal Gun Anode Corrector
CVA Corrector, Type A, Vertical Gun Anode Corrector
CHB Corrector, Type B, Horizontal Solenoid Correctors
CVB Corrector, Type B, Vertical Solenoid Correctors
CHC Corrector, Type C, Horizontal Short Corrector in Cryomodule
CVC Corrector, Type C, Vertical Short Corrector in Cryomodule
CHD Corrector, Type D, Horizontal Quad Trim Coil
CVD Corrector, Type D, Vertical Quad Trim Coil
CHE Corrector, Type E, Horizontal Dipole Trim Coil
CVE Corrector, Type E, Vertical Dipole Trim Coil
CHF Corrector, Type F, Horizontal Air Core Corrector
CVF Corrector, Type F, Vertical Air Core Corrector
CHG Corrector, Type F, Horizontal Corrector on B Line Panofsky Quad
CVG Corrector, Type F, Vertical Corrector on B Line Panofsky Quad
CHS Corrector, Type S, Horizontal Scanning Coil for Emittance Measurement System
CVS Corrector, Type S, Vertical Scanning Coil for Emittance Measurement System
CHT Corrector, Type S, Horizontal Single Scanning Coil, not part of EMS
CVT Corrector, Type S, Vertical Single Scanning Coil, not part of EMS
CHJ Corrector, Type J, Horizontal Large bore, window-frame corrector
CVJ Corrector, Type J, Vertical Large bore, window-frame corrector
QUA Quadrupole, Type A Panofsky Quad
QUB Quadrupole, Type B Short Panofsky Quad
QUC Quadrupole, Type C 2.5" pipe (Dump) Quad
QUD Quadrupole, Type D 5" pipe (Dump) Quad
SLA Solenoid, Type A  
SLB Solenoid, Type B  
RST Raster CESR Sextupole with 3 Phase Drive
Electronic Hardware
MCP Magnet Crate Bulk Power Supply
HES Hall Effect Sensor


IOD All in/out intrumentation devices (Screens, slits, Faraday cups)
SYX Screen, Yag w/o RF Shield
SYR Screen, Yag with RF Shield
SYZ Screen, Yag, Special Merger Magnet
SDX Screen, Diamond w/o RF Shield
SDR Screen, Diamond, with RF Shield
SBX Screen, BeO, w/o RF Shield
SBR Screen, BeO, with RF Shield
STR Tranistion Radiation Screen with RF Shield
SLH Slit, Hoizontal
SLV Slit, Vertical
BPA Beam Position, Type A Inner diameter = 2.700"
BPB Beam Position, Type B Inner diameter = 2.370"
BPC Beam Position, Type C Inner diameter = 1.375"
BPG Beam Position Global Control
BPS Beam Position Monitor Power Supply
BCM Beam Current Monitor Same Vacuum hardware as BPM
WSF Wire Scanner, Flying
FCA Faraday Cup, Type A Insertable, RF Shielded
FCB Faraday Cup, Type B Stationary FC at end of B1 line,\ a.k.a. Tune-up Dump
DQD Quadrant Detector Dump Quadrant Detector
PAM Pico-Amp Meter  
IVA Current to Voltage Amplifier, S5570
EMS Emittance Measurement System  


CLW Water Cooling System Closed Loop
AVF Air Vent Fan For Closed Loop Cooling System
WLD Water Leak Detector For Dump Cooling
PRO Proteus Gauge With GPM and Temp


Ion Pumps
IPA Ion Pump, Type A 400 liters/sec
IPB Ion Pump, Type B 40 liters/sec
IPC Ion Pump, Type C 100 liters/sec
IPD Ion Pump, Type D 140 liters/sec
IPE Ion Pump, Type E 60 liters/sec
IPF Ion Pump,. Type F 500 liters/sec
IPH Ion Pump,. Type H 20 liters/sec
NEG/Ion Pumps
IPI NEG/Ion pump, Type I SAES NEXTorr D100-5
IPJ NEG/Ion pump, Type J SAES NEXTorr D200-5
IPK NEG/Ion pump, Type K SAES NEXTorr D300-5
IPL NEG/Ion pump, Type L SAES NEXTorr D500-5
IPM NEG/Ion pump, Type M SAES NEXTorr D1000-10
IPN NEG/Ion pump, Type N SAES CapaciTorr D100
IPO NEG/Ion pump, Type O SAES CapaciTorr D200
Ion Gauges
IGA Ion Gauge, Type A, Extractor Leybold IONVAC IM540
IGB Ion Gauge, Type B, Cold Cathode Controller: HPS Model MKS-937
IGC Ion Gauge, Type C Controller: Granville-Phillips 358
Pirani Gauges
PGA Pirani Gauge, Type A
PGB Pirani Gauge, Type B Bakeable
Convectron Gauges
CNV Convectron Gauge, GP 275 Controller: Granville-Phillips 375
RGA Residual Gan Analyzer
Gate Valves
GVA Gate Valve, Type A
GVB Gate Valve, Type B DM40 Gate Valve w/o RF Shielding
TCK Thermocouple K Type
TCT Thermocouple T TYpe

Personnel/Equipment Protection

RDM Radiation Monitor
RMA Radiation Monitor Type A (PMT+Crystal)
BLM Beam Loss Monitor
BLC Beam Loss CsI monitor
PRM Perimeter Monitor
LBI Light Beam Interlock
IRB Interlock Reset Box
IRC Interlock Radiation Chain
MRC Main Reset Chain
FSD Fast Shut Down
INT Interlock
EKY Enable (bypass) Keys
MKY Machine Access Keys
MSP Machine Stop Chain
SAS Secure Area Switch


TCK Thermocouple, Type K
TRA Temperature Sense Resistor, Type A
TDA Temperature Sense Diode, Type A
TSW Temperature Switch
HTR Heater
FIA Flow Indicator, Type A, GAS, CDI 5200
FIB Flow Indicator, Type B, GAS, TSI 4226-01-01
PIA Pressure Indicator, Type A
FSW Flow Switch
GMS Gas Moisture Sensor
LLA Liquid Level A
LLH Liquid Level Helium
LLN Liquid Level Nitrogen
VSD Variable Speed Drive
CCG Cold Cathode Gauge
VPS Valve, Pneumatic/Solenoid Operated
VPC Valve, Pneumatic/Controller
VMA Valve, Manual
VJT Valve, Joule-Thompson
VEX Valve, Exhaust
SMC Siemens S353 Process Controller
IVC ICM/HEX CAN Insulation Vacuum Control Ready Chain
Gas Pumps
GPA Roots Pump
GPB Rotary Pump
GPC Turbo-Molecular Vacuum Pump Control
GPD Scroll Pump, Turbo Backing
Purity Monitors
NNP N2 Purity Monitor
OOP O2 Purity Monitor


GHV Gun High Voltage Power Supply
GCM Gun Current Monitor
PWC AC Power Conditioner
QES QE Scan motors
SF6 SF6 Gas/ High Pressure Chamber


CTB Buncher Cavity
CTC Coupler Test Cryostat
CTD Deflecting Cavity
IOT Inductive Output Tube System
KLY Klystron
HYB Hybrid Motor
PHS Wave Guide Phase Shifter
TUN Tuner
CPL Coupler


SSH Slow Shutter
ASH All Shutters
ENC Encoder wheel
FLW Filter Wheel
FQC Frequency Counter
FSH Fast Shutter
NPZ NanoPZ Controller
PCL Pockels Cell
PMA NovaII Power Meter
POL Polarizer
PHA Pin Hole, Adjustable
QDD Quadrant Diode Detector
LAR Laser, Argon


TCT Themocouple, Type T
CLT Cryogenic Linear Temperature Sensor
PTA Platinum 100 Temperature Sensor
PTB Platinum 1000 Temperature Sensor
TAB Allen Bradley Temperature Sensor
TIR IR Temperature Sensor


BAR Building Air
W65 65 Degree Water
W85 85 Degree Water
WRN 85 Degree Water Return
AC4 480 VAC
AC2 208 VAC
AC1 120VAC
BPR Barometric Pressure Sensor
RHA Relative Humidity Sensor
LKD Leak Detector

EPICS Pseudo-Records

These are other names of EPICS records that can be set for special purposes

Magnet Currents

For a magnet with EPICS pv name "MAGNET" there are:

MAGNET_cmd Current command value
MAGNET_rbdk Current read back value
MAGNET_V_rbdk Voltage read back value
MAGNET_cmd.DRVH Current power supply max
MAGNET_cmd.DRVL Current power supply min
MAGNET_cmd.HOPR Current max shown to operator
MAGNET_cmd.LOPR Current min shown to operator

Calibration Info

MAGNET_L Magnet length
MAGNET_field Magnet field (derived)
MAGNET_field_scale Calibration factor in T/A or (T/m)/A


EPICS IOCs can apply a degaussing procedure whenever a magnet is commanded to a target current. For every desired magnet, there are now several new EPICS records:

degauss:MAGNET_cmd Current command value with degauss procedure applied
degauss:MAGNET_status FLAG indicating degauss process is active or magnet ready
degauss:MAGNET_Npts Number of steps to take in degauss process
degauss:MAGNET_pause Pause [sec] between degauss steps
degauss:MAGNET_amplitude maximum Amplitude [amps] of the degauss step
degauss:MAGNET_no_zero_cross FLAG if true, prevents sign changes during degauss waveform
With these new records, one can still use the usualy MAGNET_cmd and MAGNET_rdbk as before - these are handled by a separate IOC. However, if one wants to set a magnet current with degauss on, then simply caput to the corresponding record:

caput degauss:MAGNET_cmd target_value

This will start the degauss procedure, utlimately setting MAGNET_cmd to target_value when finished. When this is called, a new thread is started which:

  1. increases the EPICS pv degauss:count by 1
  2. closes the laser shutter
  3. sets degauss:MAGNET_status to "BUSY"
  4. The magnet is then commanded setting the MAGNET_cmd to target_value + degauss:MAGNET_amplitude*(1 - k)*sign, where k = 0,....,1 in degauss:MAGNET_Npts steps and sign is +/- 1 alternating each step. Once the magnet is commanded, the thread sleeps for degauss:MAGNET_period before the next iteration. Once the target value is reached, the thread
  5. sets degauss:MAGNET_status to "READY"
  6. decrease degauss:count by 1
  7. if degauss:count = 0, open the laser shutter.

Because the variable degauss:count is written to by each new degaussing thread, a python lock object is used for steps 1-3 and 5-7 allowing only one thread to execute those blocks of code at a time, preventing (at least one) race condition.

This feature includes all CBETA magnets but requires measurements to determine the correct degaussing parameters for each magnet type.
Topic revision: r8 - 19 Dec 2019, StephenBrooks
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