Lakeshore Learning Materials 622 - Manual (Page 11)

Lake Shore Model 620/622/623/647 Magnet Power Supply User’s Manual
Introduction 1-1
CHAPTER 1
INTRODUCTION
1.0 GENERAL
This chapter covers Features (Paragraph 1.1), Specifications (Paragraph 1.2), and Operating Characteristics
(Paragraph 1.3).
1.1 FEATURES
• True, Four-Quadrant Bidirectional Power Flow: Operate current or voltage as a source or a sink in
either positive or negative polarities. Sink power returns to the AC line instead of dissipating through an
energy absorber.
• Low Noise, High Stability Current Regulation: Analog output control uses a precision shunt for current
stabilization to better than 50 PPM of full-scale current over an 8-hour period.
• ±50 A, ±5 V (Model 620), ±125 A, ±30 V (Model 622), ±155 A, ±30 V (Model 623),
or ±72 A, ±32 V (Model 647), Constant Current Output:
1. Programming resolution for Models 620/622/647 is 1.0 mA and 1 mV.
2. Programming resolution for the Model 623 is 1.2 mA and 1 mV.
• No current reversal switch required: Output current reversal is smooth and continuous with excellent
near zero current performance.
• Remote and local sensing of output voltage: Compensates for voltage drops in the output leads.
• Quiet switched-mode design: Results in a highly efficient, lightweight unit capable of air cooling.
• Front Panel Graphic Display: Allows continuous display of output while setting parameters from the
menu-driven keypad. Operating parameters that can be set and monitored are:
1. Output current and compliance setting.
2. Output current and voltage measurement.
3. Output current step limiting.
4. Output current zeroing.
5. Output ramp programming.
6. Status
reporting.
7. Persistent switch heater control (with optional Model 6228 Card).
8. Liquid Helium level and Field monitoring (with optional Model 6226/6476 Card).
• Four methods of setting and monitoring all operating parameters:
1. From front panel.
2. From remote interfaces.
3. Through analog inputs and outputs.
4. Through optional Lake Shore MPS Driver Software.
• Automatic Mode: Easily controls Superconducting Magnets using the Model 6228 Persistent Switch
Heater Option Card.
• IEEE-488 Interface Option
• Model 6226/6476 Liquid Helium Level/Gaussmeter Input Option Card
• Model 6228 Persistent Switch Heater Option Card
• Protection: Overvoltage/Quench protection circuits which limit or turn off the MPS output, or turn off the
input in the event of an abnormal condition; current step limit exceeded; internal overtemperature; AC line
loss detection; remote inhibit; output power exceeded. Front panel annunciators, an audio alarm, and a
contact closure indicate faults.