SLAC 5045 Klystron Modulator Training Course Session 7

1
SLAC 5045 Klystron Modulator Training
CourseSession 7
2
Purpose of Course

• To provide for engineering and maintenance
  personnel a resource to aid in the improvements
  and upkeep of the 5045 klystron modulators.

3
Course Structure

• There will be classes beginning 5/29/02 and every
  three weeks thereafter for ten total sessions.
• Each class will begin with a description of the
  design of a modulator subsystem.
• Each class will end with a time for questions and
  discussions relating to the maintenance and
  troubleshooting of the subsystem.
• These sessions are meant to be interactive!
  Please come to ask questions and to share your
  modulator know how.

4
SLAC 5045 Klystron Modulator Training Course
Syllabus

• Introduction 5/29/02
• Modulator Input Power 6/19/02
• Modulator Power Supplies 7/10/02
• Modulator Pulse Forming Network 7/31/02
• Modulator Thyratron Switch 8/21/02
• Modulator Cables 9/11/02
• Modulator Controls Diagnostics 10/3/02
• Modulator Interlocks 10/23/02
• Modulator Safety 11/13/02
• Anomalous Modulators 12/4/02

5
References

• The Stanford Two-Mile Accelerator, R.B. Neal,
  1968 W.A. Benjamin, Inc.
• Conversation with Jim Craft
• Conversation with Paul Hart

6
Modulator Front View
7
Klystron and Modulator
Note Taken from SLAC Virtual Visitor Center
8
Modulator Block Diagram
Note Taken from The Stanford Two-Mile
Accelerator, R.B.Neal, 1968
9
Open Modulator Cabinet
Step Start Resistors 600VAC Circuit
Breaker Filter Capacitors Contactors Full Wave
Bridge Rectifier De-Qing Chassis Power
Supply AC Line Filter Networks Power
Transformer (T20)
Energy Recovery Circuit Capacitor Discharge
Switch De-spiking Coil Charging Diode Pulse
Forming Network Anode Reactor Thyratron Keep
Alive Power Supply Charging Transformer
10
Thyratron Triggering
PIOP
MKSU
SCR T.D.
Thyratron
2 kV into 50 ohm 4 kV into Open Circuit 1.5 uS
FWHM 40 nS Rise time lt 1 nS Jitter Inhibits
triggers on EOLC Sends TOC data to MKSU
40 V
NIM
11
External Cable List

• HVAC Input
• Control Power Input
• Ground Wire
• Fire Alarm
• Trigger
• VVS Reference Voltage
• MKSU/IC
• Klystron Pulse Tank
• Pulse Cable
• Obsolete Cables
• Red indicates Diagnostic and Control Cables

12
External Cables
13
Modulator Input Power Connections
14
Modulator Interlock and Control Connections
15
Modulator Output Power Connections
16
Pulse Cable Testing
17
Modulator Wiring
18
More Modulator Wiring
19
Modulator Wiring Etc.
20
Modulator Internal Wiring Drawings

• EI-730-600-00-C11 Modulator 6575 Interconnection
  Diagram
• WD-730-620-01-C0 Modulator 6575 Variant Relay
  Panel Wiring Diagram
• WD-730-629-00-C12 Modulator 6575 Control Panel
  Wiring Diagram
• WD-730-630-00-C5 Modulator 6575 Power Panel
  Wiring Diagram
• WD-730-632-00-C3 Thyratron Power Chassis
  Modulator 6575 WD-730-634-00-C3 Modulator 6575
  Core Bias Pwr Supply Pnl Wiring Diagram

21
Modulator Diagnostics Controls

• Modulator Local Diagnostics
• Indicator Lights
• Meters
• Diagnostic Ports
• Modulator Local Controls
• Modulator Remote Control Diagnostics

22
Indicator Lights

• Diagnostic
• 600VAC
• Control Voltage
• SCRTD
• Power
• Trigger Present
• HV Output Present
• Trigger Rate Overload
• Thyratron Fault
• Internal Fault
• EOLC Signal Present
• EOLC Fault
• Status
• Reset
• Ready
• HV On
• Energy Recovery On (Back Wall)
• Klystron Beam (Not Used)

23
Modulator Power Supply Front Panel Controls and
Diagnostics
24
Meters

• De-Qing SCR Current
• DC PS Voltage
• DC PS Current
• Klystron Filament Current
• Klystron Filament Voltage
• Core Bias Current
• Klystron Filament Hour Meter
• HV Hour Meter
• Thyratron Heater Reservoir Voltage Meter
  (Switched)

25
Modulator Power Supply Front Panel Controls and
Diagnostics
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Diagnostic Ports

• Modulator
• Grid Trigger
• PFN Voltage
• De-Qing Divider Voltage
• Reference Voltage
• P.T. Primary Current (Not Used)
• Scope Trigger
• EOL Clipper Current
• FT-20 (Back)
• De-Q SCR Trigger (Back)
• Thyratron Reservoir/Filament Voltage (Switched)
• SCRTD Output Pulse
• Pulse Tank
• Beam Voltage
• Beam Current

27
Modulator Power Supply Front Panel Controls and
Diagnostics
28
MKSU and Scope Triggers
29
SCRTD Triggers
30
Grid Trigger
31
FT-20
32
PFN Voltage
33
High Voltage Power Supply
Note Taken from The Stanford Two-Mile
Accelerator, R.B.Neal, 1968
34
De-Qing PFN Voltages
35
De-Q SCR
36
EOLC Current
37
Beam Voltage Current
38
Modulator Local Controls

• Filament Time Delay Relay
• Key Switch
• Fault Counter Setting
• Reset
• HV On
• HV Off
• Emergency Off
• Cassel Box Local/Remote Switch
• Klystron Filament Current Adjustment
• Core Bias Current Adjustment
• De-Qing Current Adjustment
• Energy Recovery On/Off

39
Modulator Power Supply Front Panel Controls and
Diagnostics
40
Modulator Remote Control

• VVS AC voltage to Modulator
• VVS Reference voltage to Modulator
• Modulator Trigger

41
VVS Control Block Diagram
Modulator
30-60VDC
FT-12 DQing Ref. Voltage View
Master Substation 12.47kV
Monitor Rectifier
J830
J-25
s
60-120VDC
60-120VDC
Reference Power Supply
Remote/Local Control Chassis
23kV
300-600VAC
60-120VDC
CAMAC
Klystron
Linac
From Jim Craft
42
Variable Voltage Substation (VVS)

• Taken from The Stanford Two-Mile Accelerator,
  R.B. Neal, 1968 W.A. Benjamin, Inc.

43
VVS Control
VVS Control is located in the IC Alcove
44
RF Drive/Timing/Trigger System
45
RF System
MKSU
Phase Amplitude Detector
Parallel Input Output Processor
Trigger
Cassel Box
Modulator
CAMAC
Isolator Phase Shifter Attenuator
Klystron
Sub-Booster
SLED
Focus Magnet Power Supply
Accelerator Sections
46
Modulator Klystron Support Unit (MKSU)
Monitors RF system and modulator interlocks and
inhibits triggers to the modulator upon fault
conditions. It also acts as an interface from the
modulator to the CAMAC based control system,
enabling remote operation of the modulator and
the collection of data.
47
MKSU Controls

• Remote Control
• Modulator On, Off, Reset
• SLED Tune/De-Tune
• Local Control in Maintenance Mode
• Modulator trigger On, off, and rate.
• RF drive
• Beam pulse with respect to Sub-booster RF timing

48
MKSU Diagnostics

• Fast Time Plots Beam Voltage, Beam Current,
  Amplitude Jitter, Phase Jitter.
• RF Component and modulator interlock status.
• Error Log.
• Modulator Statuses HVOC (not connected), EOLC
  Fault, Trigger Over-current, Ext. Fault, Fault
  Lockout, HV Ready, Mod. Klystron Heater Delay,
  Mod. Control Power Fault, Mod. HV On, Modulator
  in Local (red button on Cassel box).

49
Klystron Status Display
Note Critical stations have tighter tolerances
on phase jitter and amplitude jitter.
50
Cassel Box
To Modulator Controls 120VAC
From MKSU Command -24VDC
From Modulator Status 120VAC
To MKSU Status -24VDC
51
Tuning the Control System PEP-II Index
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Tuning the Control System Klystron Index
53
Tuning the Control System Linac Klystron Panel
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PIOP Data Display
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Tuning the Control System Linac Klystron Panel
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Fast Time Plot Full Scale
57
High Gain Fast Time Plot with Klystron Timing Data
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Beam Voltage Jitter Plot
59
Beam Current History
60
Phase Jitter History