Service manual

5
TABLE OF CONTENTS
Introduction ............................................................................................................................................................................7
Scope ....................................................................................................................................................................................7
Calibration and Verification ............................................................................................................................................. 7
Troubleshooting................................................................................................................................................................ 7
Principles of Operation..................................................................................................................................................... 7
Replaceable Parts.............................................................................................................................................................. 7
Circuit Diagrams...............................................................................................................................................................7
Safety Considerations...........................................................................................................................................................7
Manual Revisions ................................................................................................................................................................. 8
Calibration and Verification.................................................................................................................................................. 9
Introduction........................................................................................................................................................................... 9
Test Equipment Required ..................................................................................................................................................... 9
Operation Verification Tests.................................................................................................................................................9
Calibration Procedure........................................................................................................................................................... 9
Initial Setup..................................................................................................................................................................... 12
Performance Tests ..............................................................................................................................................................16
Measurement Techniques ............................................................................................................................................... 16
Constant Voltage (CV) Tests..........................................................................................................................................18
Constant Current (CC) Tests........................................................................................................................................... 24
Troubleshooting.................................................................................................................................................................... 27
Introduction......................................................................................................................................................................... 27
Initial Troubleshooting Procedures.....................................................................................................................................27
Electrostatic Protection.......................................................................................................................................................29
Repair and Replacement.....................................................................................................................................................29
A2 Control Board Removal............................................................................................................................................ 30
A4 FET Board Removal ................................................................................................................................................. 30
A5 Diode Board Removal...............................................................................................................................................31
A3 Front Panel Board Removal...................................................................................................................................... 31
A1 Main Board Removal................................................................................................................................................ 31
Overall Troubleshooting Procedure....................................................................................................................................32
Using the Tables ............................................................................................................................................................. 33
Main Troubleshooting Setup .......................................................................................................................................... 33
Troubleshooting No-Output Failures.............................................................................................................................. 36
Front Panel Troubleshooting........................................................................................................................................... 36
Troubleshooting Bias Supplies .......................................................................................................................................38
Power Section Blocks..................................................................................................................................................... 40
Troubleshooting AC-Turn-on Circuits............................................................................................................................40
Troubleshooting PWM & Clock..................................................................................................................................... 41
Troubleshooting DC-To-DC Converter.......................................................................................................................... 42
Troubleshooting Down Programmer .............................................................................................................................. 42
Troubleshooting CV Circuit ...........................................................................................................................................44
Troubleshooting CC Circuit............................................................................................................................................ 44
Troubleshooting OVP Circuit......................................................................................................................................... 45
Principles of Operation ........................................................................................................................................................47
Autoranging Power............................................................................................................................................................. 47
Overview............................................................................................................................................................................. 47
System Description............................................................................................................................................................. 47
Regulation & Control Subsystem ....................................................................................................................................... 48
Protection Subsystem.......................................................................................................................................................... 53
Input Power Subsystem ...................................................................................................................................................... 53