American Magnetics 05120PS-430-601 Manual

American Magnetics, Inc.
P.O. Box 2509, 112 Flint Road, Oak Ridge, TN 37831-2509, Tel: [phone], Fax: [phone]
Rev. 10, August 2021
BIPOLAR POWER SUPPLY
SYSTEMS
MODELS 05120PS-430-601, 05240PS-430-601,
05360PS-430-601, 05600PS-430-601 &
03300PS-430-601
INCLUDING HIGH-STABILITY OPTION
INSTALLATION, OPERATION, AND
MAINTENANCE INSTRUCTIONS
EXCELLENCE IN MAGNETICS AND CRYOGENICS

REV 10 III
AMERICAN MAGNETICS, INC. TABLE OF CONTENTS
Foreword .................................................................................. ix
Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Contents of this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Applicable Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . x
General Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Cryogen Safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Treating Cold Burns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xii
Handling Cryogenic Liquids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xii
Material Safety at Cryogenic Temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xii
Magnet Quenches in LHe-Cooled Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Risk of Explosion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Magnetic Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Safety Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiv
Minimum Recommended Safety Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiv
Safety Legend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xv
Introduction ...............................................................................1
Integrated Bipolar Power Supply System Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Digitally-Controlled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Superior Resolution and Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
High-Stability Option. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Intuitive Human-Interface Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Flexibility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Standard Remote Interfaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Programmable Safety Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Condition-Based Magnet Auto-Rampdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Bipolar Systems General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Model 05120PS-430-601 Power Supply System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Model 05240PS-430-601 Power Supply System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Model 05360PS-430-601 Power Supply System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Model 05600PS-430-601 Power Supply System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Model 03300PS-430-601 Power Supply System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Model 430 Front Panel Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Model 430 Rear Panel Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Power Supply Unit Front Panel Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

iv REV 10
AMERICAN MAGNETICS, INC. TABLE OF CONTENTS
Model 601 Energy Absorber Front Panel Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Bipolar System Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Model 430 Specifications @ 25 °C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Operating Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Single-Quadrant Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Dual-Quadrant Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Four-Quadrant Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Installation............................................................................... 23
Inspecting and Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Power Supply System Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Power Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Changing the Model 430 Programmer Operating Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Collecting Necessary Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
System Interconnects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Shunt-Based Bipolar Power Supply System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
High-Current, High-Stability Bipolar Power Supply System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Special Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Superconducting Magnets with No Persistent Switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Short-Circuit or Resistive Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Power-Up and Test Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Operation ................................................................................ 45
System Power On/Off Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Model 430 Programmer Power On/Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Energizing the Power Supply and Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Model 430 Programmer Default Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Field / Current Display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Voltage Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Status Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Main Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Entering Numeric Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

REV 10 V
AMERICAN MAGNETICS, INC. TABLE OF CONTENTS
Using the Fine Adjust Knob . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Selecting Picklist Values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
Single-key Commands / Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Persistent Switch Control Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Target Field Setpoint Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Ramp / Pause Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Ramp To Zero Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
SHIFT+key Commands / Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
Ramp Rate (Shift+1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Voltage Limit (Shift+2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Reset Quench (Shift+3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Increment Field (Shift+4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Field <> Current (Shift+5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Decrement Field (Shift+6). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Field Units (Shift+7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Persistent Switch Heater Current (Shift+8). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Stability (Shift+9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Vs <> Vm (Shift+0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Volt Meter (Shift+.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Fine Adjust (Shift +/-) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Shift + Persist. Switch Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
LED Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
Power-on Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Magnet Status Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Shift Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Setup Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
Entering / Exiting Setup Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Menu Navigation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Setup Submenu Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
Supply Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Load Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Switch Submenu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Protection Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Misc Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Net Settings Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Net Setup Submenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Example Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108

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AMERICAN MAGNETICS, INC. TABLE OF CONTENTS
Ramping Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Ramping States and Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Manual Ramping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Automatic Ramping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Ramping to Zero . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Fine Adjust of Field / Current in Holding Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Persistent Switch Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Procedure for Initial Heating of the Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Procedure for Entering Persistent Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Procedure for Exiting Persistent Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Toggling the State of the Persistent Switch Heater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Ramping Functions Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Quench Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Quench Detection Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
External Quench Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Disabling Internal Quench Detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
External Rampdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
External Rampdown while in Persistent Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
External Rampdown while not in Persistent Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Summary of Limits and Default Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Remote Interface Reference................................................... 129
SCPI Command Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Programming Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
SCPI Language Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
SCPI Status System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Status Byte Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Standard Event Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Command Handshaking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
RS-232 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Serial Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Termination Characters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Ethernet Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Ethernet Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Termination Characters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Port Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

REV 10 VII
AMERICAN MAGNETICS, INC. TABLE OF CONTENTS
Telnet Port 23 Broadcast Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Command Reference. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .148
System-Related Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Status System Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Supply Setup Configuration Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
Load Setup Configuration Commands and Queries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Switch Setup Configuration Commands and Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Protection Setup Configuration Commands and Queries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Misc Setup Configuration Commands and Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Lock Commands and Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Net Setup Configuration Commands and Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Ramp Target/Rate Configuration Commands and Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Measurement Commands and Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
Ramping State Commands and Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Switch Heater Command and Query . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Quench State Commands and Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Rampdown State Commands and Queries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Trigger Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179
Command Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
Query Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
Execution Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
Device Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Remote Applications and Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185
Magnet-DAQ: Comprehensive Model 430 Remote Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
SCPI-Based Communication via RS-232 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
SCPI-Based Communication via Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
Service ...................................................................................193
System Component Routine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193
Model 08150PS Power Supply Routine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Model 601 Energy Absorber Routine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Model 430 Firmware Upgrades. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194
Manually Upgrading the Firmware via FTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
Troubleshooting Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197
Electrostatic Discharge Precautions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
Hints for Commonly Encountered Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198

viii REV 10
AMERICAN MAGNETICS, INC. TABLE OF CONTENTS
Additional Technical Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Return Authorization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Appendix ............................................................................... 207
Magnet Station Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
LHe Level / Temp Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Programmer Shunt Terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
Current Transducer Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Program Out Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
Quench I/O Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
External Quench Detection Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
External Rampdown Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
External Quench Detection Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Auxiliary Inputs Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Ethernet Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217
RS-232 Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Abbreviations and Acronyms used in this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
Short-Sample Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Power Supply Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
Energy Absorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Model 601 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Connecting Multiple Model 601 Energy Absorbers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Index...................................................................................... 231

REV 10 IX
AMERICAN MAGNETICS, INC. FOREWORD
Foreword
PURPOSE AND SCOPE
This manual contains the operation and maintenance instructions for the
American Magnetics, Inc. Bipolar Power Supply Systems with optional
high-stability via a zero flux current sensing system. The user is
encouraged to contact an authorized AMI Technical Support
Representative for information regarding specific configurations not
explicitly covered in this manual.
CONTENTS OF THIS MANUAL
Introduction introduces the reader to the functions and characteristics
of the Model 430 Power Supply Programmer and the Power Supply
System. It provides illustrations of the front and rear panel layouts as
well as documenting the performance specifications. Additional
information is provided in the form of system circuit diagrams.
Installation describes how the Model 430 Power Supply Programmer is
unpacked and installed in conjunction with ancillary equipment in typical
superconducting magnet systems. Block-level diagrams document the
interconnects for various system configurations.
Operation describes how the Model 430 Programmer is used to control
a superconducting magnet. All Model 430 Programmer displays and
controls are documented. The ramping functions, persistent switch
heater controls, and the quench detect features are also presented.
Remote Interface Reference documents all remote commands and
queries available through the Model 430 Programmer RS-232 and

XREV 10
AMERICAN MAGNETICS, INC. FOREWORD : APPLICABLE HARDWARE
Ethernet interfaces. A quick-reference summary of commands is
provided as well as a detailed description of each.
Service provides guidelines to assist the user in troubleshooting
possible system and Model 430 Programmer malfunctions. Information
for contacting AMI Technical Support personnel is also provided.
Appendix provides additional details and/or procedures in the following
areas:
• Model 430 Programmer rear panel connectors.
• Individual power supply unit specifications.
• Model 601 specifications.
• Establishing RS-232 or Ethernet communications with the Model 430.
• Model 430 firmware upgrade procedures.
• Abbreviations and acronyms used in this manual.
• Optional Short-Sample operational mode.
APPLICABLE HARDWARE
The Model 430 Programmer has been designed to operate with a wide
variety of switch mode and linear power supplies from a variety of
manufacturers. However, not all compatible power supplies have been
tested. The Model 430 Programmer has been tested and qualified with
the following power supplies or power supply systems:
AMI Model 12100PS switching power supply (12 V @ 100 A)
AMI Model 12200PS switching power supply (12 V @ 200 A)
AMI Model 7.5-140PS switching power supply (7.5 V @ 140 A)
AMI Model 10100PS switching power supply (10 V @ 100 A)
AMI Model 10200PS switching power supply (10 V @ 200 A)
AMI Model 08150PS switching power supply (1200 Watt)
AMI Model 03300PS (multiple Model 08150PS w/ Energy Absorbers; ±3 V @ 300 A)
AMI Model 05100PS (Model 08150PS w/ Energy Absorber; ±5 V @ 100 A)
AMI Model 05120PS (Model 08150PS w/ Energy Absorber; ±5 V @ 120 A)
AMI Model 05240PS (multiple Model 08150PS w/ Energy Absorbers; ±5 V @ 240 A)
AMI Model 05360PS (multiple Model 08150PS w/ Energy Absorber; ±5 V @ 360 A)
AMI Model 05400PS switching power supply w/ Energy Absorber (±5 V @ 400 A)
AMI Model 05600PS (multiple Model 08150PS w/ Energy Absorber; ±5 V @ 600 A)
AMI Model 4Q06125PS 4-quadrant switching power supply (±6 V @ ±125 A)
AMI Model 4Q06250PS 4-quadrant switching power supply (±6 V @ ±250 A)
AMI Model 4Q12125PS 4-quadrant switching power supply (±12 V @ ±125 A)
AMI Model 4Q05100PS 4-quadrant switching power supply (±5 V @ ±100 A)
Xantrex Model XFR 12-100 switching power supply (12 V @ 100 A)
Xantrex Model XFR 12-220 switching power supply (12 V @ 220 A)
Xantrex Model XHR 7.5-130 switching power supply (7.5V @ 130 A)
Hewlett-Packard 6260B linear power supply (10 V @ 100 A)
Kepco BOP 20-5M 4-quadrant linear power supply (±20 V @ ±5 A)
Kepco BOP 20-10M 4-quadrant linear power supply (±20 V @ ±10 A)

REV 10 XI
AMERICAN MAGNETICS, INC. FOREWORD : GENERAL PRECAUTIONS
Kepco BOP 20-20M 4-quadrant linear power supply (±20 V @ ±20 A)
Accel Instruments TS250-8 4-quadrant power supply ((±7 V @ ±5 A)
Consult with an AMI Technical Support Representative for other
approved power supplies.
GENERAL PRECAUTIONS
CRYOGEN SAFETY The two most common cryogenic liquids used in superconducting
magnet systems are nitrogen (LN2) and helium (LHe). Both of these
cryogens are extremely cold at atmospheric pressure (321°F and 
452°F, respectively). The following paragraphs outline safe handling
precautions for these liquids.
Personnel handling cryogenic liquids should be thoroughly instructed
and trained as to the nature of the liquids. Training is essential to
minimize accidental spilling. Due to the low temperature of these
materials, a cryogen spilled on many objects or surfaces may damage
the surface or cause the object to shatter, often in an explosive manner.
Inert gases released into a confined or inadequately ventilated space
can displace sufficient oxygen to make the local atmosphere incapable
of sustaining life. Liquefied gases are potentially extreme suffocation
hazards since a small amount of liquid will vaporize and yield a very
large volume of oxygen-displacing gas. Always ensure the location
where the cryogen is used is well ventilated. Breathing air with
insufficient oxygen content may cause unconsciousness without
warning. If a space is suspect, purge the space completely with air and
test before entry. If this is not possible, wear a forced-air respirator and
enter only with a co-worker standing by wearing a forced-air respirator.
Cryogenic liquids, due to their extremely low temperatures, will also burn
the skin in a similar manner as would hot liquids. Never permit cryogenic
liquids to come into contact with the skin or allow liquid nitrogen to soak
clothing. Serious burns may result from careless handling. Never touch
uninsulated pipes or vessels containing cryogenic liquids. Flesh will stick
to extremely cold materials. Even nonmetallic materials are dangerous
to touch at low temperatures. The vapors expelled during the venting
process are sufficiently cold to burn flesh or freeze optic tissues.
Insulated gloves should be used to prevent frost-bite when operating
valves on cryogenic tanks. Be cautious with valves on cryogenic
systems; the temperature extremes they are typically subjected to cause
seals to fail frequently.

XII REV 10
AMERICAN MAGNETICS, INC. FOREWORD : GENERAL PRECAUTIONS
TREATING COLD BURNS In the event a person is burned by a cryogen or material cooled to
cryogenic temperatures, the following first aid treatment should be given
pending the arrival and treatment of a physician or other medical care
worker:
1. If any cryogenic liquid contacts the skin or eyes, immediately flush the
affected area gently with tepid water (102°F  105°F, 38.9°C  40.5°C) and
then apply cold compresses.
2. Do not apply heat. Loosen any clothing that may restrict circulation. Apply a
sterile protective dressing to the affected area.
3. If the skin is blistered or there is any chance that the eyes have been
affected, get the patient immediately to a physician for treatment.
HANDLING CRYOGENIC LIQUIDS
Containers of cryogenic liquids are self pressurizing (as the liquid boils
off, vapor pressure increases). Hoses or lines used to transfer these
liquids should never be sealed at both ends (i.e. by closing valves at
both ends).
When pouring cryogenic liquids from one container to another, the
receiving container should be cooled gradually to prevent damage by
thermal shock. The liquid should be poured slowly to avoid spattering
due to rapid boil off. The receiving vessel should be vented during the
transfer.
MATERIAL SAFETY AT CRYOGENIC TEMPERATURES
Introduction of a substance at or near room temperature into a cryogenic
liquid should be done with great caution. There may be a violent gas
boil-off and a considerable amount of splashing as a result of this rapid
boiling. There is also a chance that the material may crack or
catastrophically fail due to forces caused by large differences in thermal
contraction of different regions of the material. Personnel engaged in this
type of activity should be instructed concerning this hazard and should
always wear a full face shield and protective clothing. If severe spraying
or splashing could occur, safety glasses or chemical goggles along with
body length protective aprons will provide additional protection.
The properties of many materials at extremely low temperatures may be
quite different from the properties that these same materials exhibit at
room temperatures. Exercise extreme care when handling materials
cooled to cryogenic temperatures until the properties of these materials
under these conditions are known.

REV 10 XIII
AMERICAN MAGNETICS, INC. FOREWORD : GENERAL PRECAUTIONS
Metals to be used for use in cryogenic equipment application must
posses sufficient physical properties at these low temperatures. Since
ordinary carbon steels, and to somewhat a lesser extent, alloy steels,
lose much of their ductility at low temperatures, they are considered
unsatisfactory and sometimes unsafe for these applications. The
austenitic Ni-Cr alloys exhibit good ductility at these low temperatures
and the most widely used is 18-8 stainless steel. Copper, Monel®, brass
and aluminum are also considered satisfactory materials for cryogenic
service.
MAGNET QUENCHES IN LHE-COOLED SYSTEMS
When an energized superconducting magnet transitions from
superconducting state to normal state, the magnet converts magnetic
energy to thermal energy thereby rapidly converting the liquid helium to
a vapor. When this phase transformation occurs, pressures can build
rapidly in the cryostat due to the fact that one part of liquid helium will
generate 782 parts of gaseous helium at STP (standard temperature and
pressure). The cryostat must be designed to allow the generated vapor
to rapidly and safely vent to an area of lower pressure. Cryostats are
designed with pressure relief valves of sufficient capacity so as to limit
the pressure transients within the container in order to prevent damage
to the vessel. Operating a superconducting magnet in a cryostat without
properly sized relief mechanisms or disabled relief mechanism is unsafe
for the operator as well as for the equipment. If there is any doubt as to
the sufficiency of the pressure relief system, contact the manufacturer of
the magnet and cryostat for assistance.
RISK OF EXPLOSION Ensure cryogen container and/or magnet system vent relief valves are
kept clear. An improperly ventilated cryostat/system may become
blocked by ice with subsequent RISK OF EXPLOSION and uncontrolled
release of cryogens from the system. Relief valves and rupture disks
may also discharge cold gas violently without warning. Relief valves
should always be pointed in a safe direction. Care must be taken not to
disable pressure relief devices or otherwise create a condition where
pressure buildup can occur in a magnet system or cryogen container
because of the RISK OF EXPLOSION. FAILURE TO HEED THIS
WARNING COULD RESULT IN INURY OR DEATH.
MAGNETIC FIELDS The following notices should be posted to warn personnel of the dangers
of strong magnetic fields produced by superconducting magnets:
i. WARNING: The operation of medical electronic implants, such as
cardiac pacemakers, may be affected by magnetic fields, WHICH
COULD CAUSE INJURY OR DEATH.

XIV REV 10
AMERICAN MAGNETICS, INC. FOREWORD : SAFETY SUMMARY
ii. WARNING: Medical implants, such as aneurysm clips, surgical clips or
prostheses may contain ferromagnetic materials and therefore would be
subject to strong forces near a magnet. THIS COULD RESULT IN INURY
OR DEATH. In the vicinity of rapidly changing field (e.g. pulsed gradient
fields), eddy currents may be induced in the implant resulting in heat
generation.
iii. WARNING: Metal materials in someone's body as a result of an old
injury may be affected by magnetic fields in this facility. THIS COULD
RESULT IN INURY OR DEATH.
iv. WARNING: Large attractive forces may be exerted on equipment
brought near to the magnet. The force may become large enough to
move the equipment uncontrollably towards the magnet. Pieces of
equipment may become projectiles and large equipment (e.g. gas
bottles, power supplies) could trap bodies or limbs between the
equipment and the magnet. EITHER TYPE OF OBJECT MAY CAUSE
INJURY OR DEATH. The closer to the magnet you get, the larger the
force is. The larger the mass of the equipment the larger the force pulling
it.
v. CAUTION: The operation of equipment may be directly affected by the
presence of large magnetic fields. Items such as watches, tape
recorders, and cameras may be magnetized and irreparably damaged if
exposed to magnetic fields. Information encoded magnetically on credit
cards and magnetic tape including computer floppy discs, may be
irreversibly corrupted. Electrical transformers may become magnetically
saturated. Safety characteristics of equipment may also be affected.
SAFETY SUMMARY
Superconducting magnet systems are complex systems with the
potential to seriously injure personnel or equipment if not operated
according to procedures. The use of cryogenic liquids in these systems
is only one factor to consider in safe and proper magnet system
operation. Proper use of safety mechanisms (pressure relief valves,
rupture disks, etc.) included in the cryostat and top plate assembly are
necessary. Furthermore, an understanding of the physics of the magnet
system is needed to allow the operator to properly control the large
amounts of energy stored in the magnetic field of the superconducting
coil. The Model 430 Programmer has been designed with safety
interlocks to assist the operator in safe operation, but these designed-in
features cannot replace an operator’s understanding of the system to
ensure the system is operated in a safe and deliberate manner.
MINIMUM RECOMMENDED SAFETY EQUIPMENT
• First Aid kit
• Fire extinguisher rated for class C fires

REV 10 XV
AMERICAN MAGNETICS, INC. FOREWORD : SAFETY SUMMARY
• Cryogenic gloves
• Face shield
• Signs to indicate that there are potentially hazardous magnetic fields in the
area and that cryogens are in use in the area.
SAFETY LEGEND Instruction manual symbol: the product is marked with this
symbol when it is necessary for you to refer to the instruction
manual in order to protect against damage to the product or
personal injury.
Hazardous voltage symbol.
Alternating Current (Refer to IEC 417, No. 5032).
Off (Supply) (Refer to IEC 417, No. 5008).
On (Supply) (Refer to IEC 417, No. 5007).
WARNING The Warning sign denotes a hazard. It calls attention to a
procedure or practice, which if not correctly adhered to,
could result in personal injury. Do not proceed beyond a
Warning sign until the indicated conditions are fully
understood and met.
CAUTION The Caution sign denotes a hazard. It calls attention to an
operating procedure or practice, which if not adhered to,
could cause damage or destruction of a part or all of the
product. Do not proceed beyond a Caution sign until the
indicated conditions are fully understood and met.
O
I

XVI REV 10
AMERICAN MAGNETICS, INC. FOREWORD : SAFETY SUMMARY

REV 10 1
AMERICAN MAGNETICS, INC. INTRODUCTION
Introduction
INTEGRATED BIPOLAR POWER SUPPLY SYSTEM FEATURES
The AMI Model 05120PS-430-601, 05240PS-430-601, 05360PS-430-
601, 05600PS-430-601, and 03300PS-430-601 Power Supply Systems
allow an operator to manage a superconducting magnet system with
unprecedented accuracy and ease of use.
Integral components of the system include a Model 430 Programmer
with optional zero flux current sensing system (High-Stability Option),
one or more Model 601 Energy Absorbers, and one or more power
supplies to achieve the rated system output current. The system
provides a degree of flexibility and accuracy previously unavailable in an
economical commercial product.
DIGITALLY-
CONTROLLED
The Power Supply System is controlled by the microcomputer inside the
Model 430 Programmer which performs all analog data conversion, dis-
play/keypad functions, communications I/O, generation of analog pro-
gramming signals for the external power supply, and control law
computations. The Model 430 Programmer incorporates digital signal
processing (DSP) functions that provide for accurate control, low drift,
and flexibility of use.
SUPERIOR RESOLUTION
AND STABILITY
The Model 430 Programmer incorporates high-resolution converters to
translate signals between the analog and digital domains. Precision
instrumentation techniques and potentiometer-free designs are
employed throughout the Model 430 Programmer to ensure accurate
signal translation for a wide range of conditions. The magnet current is
sampled at 24-bit resolution in hardware and is software-programmable
to 15-digits resolution. All pause and hold functions are performed in the
digital domain which provides for excellent stability and drift of the pro-
grammed magnetic field.

2 REV 10
AMERICAN MAGNETICS, INC. INTRODUCTION : INTEGRATED BIPOLAR POWER SUPPLY SYSTEM FEATURES
HIGH-STABILITY
OPTION
For greater stability and accuracy, the Model 430 Programmer can be
configured with a zero-flux precision current measuring device instead of
the standard resistive shunt. This option typically increases the system
stability and accuracy by an order of magnitude. The power supply sys-
tems incorporating this technique are referred to as “high-stability” sys-
tems.
INTUITIVE HUMAN-
INTERFACE DESIGN
The Model 430 Programmer was designed to simplify the interface
where possible. All functions were analyzed and subsequently
programmed so that the most commonly used functions are addressed
with the least number of keystrokes. The menus are also presented in a
logical fashion so that the operation of the Model 430 Programmer is
intuitive to the user.
The provision of a velocity-sensitive rotary encoder on the front panel
also allows the operator to interactively fine-adjust many of the operating
parameters of the magnet system.
FLEXIBILITY The Model 430 Programmer can be configured with the supporting
hardware as a two- or four-quadrant power supply system which is able
to both supply and remove electrical energy from the superconducting
magnet system. The Model 430 Programmer is engineered to be
compatible with most power supplies with remote analog programming
capabilities.
From simple single-quadrant supplies, to more elaborate four-quadrant
units, the Model 430 Power Supply Programmer is user-configurable
such that the operational paradigm complies with the specific magnet
system requirements.
STANDARD REMOTE
INTERFACES
The Model 430 Programmer provides an RS-232 serial port as well as
an Ethernet port as standard features. All settings can be controlled via
the remote interfaces and the front panel can be remotely locked to
prevent accidental operation. The Model 430 Programmer also provides
remote trigger functions for data collection and/or logging during
operation.
PROGRAMMABLE
SAFETY FEATURES
The Power Supply System is designed to be operated from the front
panel of the Model 430 Programmer or remotely with operational
parameters which must not be exceeded for the given conditions of the
system. Once set, should an operator inadvertently attempt to take the
magnet system to an excessive magnetic field strength or charge at an
excessive voltage, the Model 430 Programmer will not accept the

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parameter and will alert the operator that a value was rejected because it
was outside the user-defined limits.
In addition, each setup parameter can be individually selected for
locking. A user-defined password is required to lock or unlock settings.
This allows an administrator to set and password protect any critical
parameters that should not be changed by the operator. Then the
administrator can be confident that an operator will not subsequently
change any of these critical parameters, and yet will be free to change
any non-critical (unlocked) parameters.
CONDITION-BASED
MAGNET AUTO-
RAMPDOWN
The Model 430 Programmer can be connected to an AMI Model 1700
Liquid Level Instrument, with the LHe measurement option, to allow
automatic rampdown of the magnet (even in persistent mode) should the
liquid helium (LHe) level drop to a preset level. This feature ensures the
magnet will be protected and not experience a quench should the LHe
level reach an unsafe level for magnet operation. A single cable is
required to use this feature and is covered in more detail on page 215 of
the Appendix. Contact AMI for more information.
In addition to low LHe level, inputs to the Model 430 Programmer can be
used with other instrumentation as well. Other uses include faults from a
cryocooler, temperature measurement limit, etc.
BIPOLAR SYSTEMS GENERAL DESCRIPTION
AMI’s bipolar power supply systems rely upon unipolar power supplies
and the AMI Model 601 Energy Absorber to achieve two-quadrant
operation (bipolar voltage only). The unipolar power supplies used in the
systems can be configured to provide various voltage and current output
within the output power limits of the supply. Therefore, the Model
08150PS power supply (0-8 VDC, 0-150 A) can be alternately
configured for 0-10 V output at a maximum current of 120 A. This a
common configuration for superconducting magnet applications as it
provides up to a +5 VDC charge rate (minus lead losses; power leads
resistance is typically around 10 milliohms).
As a unipolar power supply, the Model 08150PS can only source1 (not
sink) power. However, when the power supply is used in conjunction with
the AMI Model 601 Energy Absorber, the result is the bipolar Model
05120PS-430-601 integrated power supply system that is ideal for
1. The power supply is operating as a source if the current direction and voltage polarity are the
same (e.g. the situation that would exist when supplying a resistive load). If the voltage
polarity and current direction are opposite, the supply is operating as a sink.

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AMERICAN MAGNETICS, INC. INTRODUCTION : BIPOLAR SYSTEMS GENERAL DESCRIPTION
driving inductive loads such as large magnets or motors. The Model 601
Energy Absorber provides a -5 VDC discharge capacity.2
The power supply is controlled by a 0-10 VDC remote analog signal
supplied by the Model 430 Programmer and applied to the power supply
analog input. Programming and control of the current loop (composed of
the magnet, power supply, and Model 430 Programmer shunt or optional
zero flux current measurement device), is provided by an internal Model
430, ramp-generated current reference with parameters as set by the
user. The Model 430 continuously compares the measured current with
its internal current reference to provide precise closed-loop control of the
actual current.
The power supplies are operated in voltage-commands-voltage3
programming mode, with the Model 430 Programmer output scaled to
operate the power supply over its available voltage output range. The
Model 430 Programmer signal will continually adjust the power supply
output voltage to automatically regulate the loop current; precise linear
current control will result as long as the system voltage and current
demands do not exceed the power supply rating or load limiting
parameters.
2. This -5 VDC discharge or “reverse-bias” is continually present when operating the bipolar
power supply systems at greater than zero current. The primary energy discharge method is
by heat dissipation of the converted electrical energy.
3. Voltage reference controlling voltage output.