Lake Shore 370, Руководство пользователя

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Lake Shore Model 370 AC Resistance Bridge User’s Manual
TABLE OF CONTENTS (Continued)
Chapter/Paragraph Title Page
2.9.1.1 Sensitivity ................................................................................................................................. 2-14
2.9.1.2 Temperature Range ................................................................................................................. 2-15
2.9.1.3 Temperature Resolution ........................................................................................................... 2-15
2.9.1.4 Accuracy ................................................................................................................................... 2-15
2.9.1.5 Packaging ................................................................................................................................. 2-15
2.9.1.6 Environment ............................................................................................................................. 2-15
2.9.2 Sensor
Calibration ........................................................................................................................ 2-16
2.9.3 Sensor Installation ........................................................................................................................ 2-16
2.9.3.1 Mounting Materials ................................................................................................................... 2-16
2.9.3.2 Sensor
Location ........................................................................................................................ 2-16
2.9.3.3 Thermal Conductivity ................................................................................................................ 2-16
2.9.3.4 Contact Area ............................................................................................................................. 2-17
2.9.3.5 Contact Pressure ...................................................................................................................... 2-17
2.9.3.6 Lead Wire ................................................................................................................................. 2-17
2.9.3.7 Lead
Soldering ......................................................................................................................... 2-17
2.9.3.8 Heat Sinking Leads .................................................................................................................. 2-17
2.9.3.9 Thermal Radiation .................................................................................................................... 2-17
2.10 TEMPERATURE CONTROL ........................................................................................................... 2-17
2.10.1
Considerations For Good Control ................................................................................................. 2-18
2.10.1.1 Thermal Conductivity ................................................................................................................ 2-18
2.10.1.2 Thermal Lag ............................................................................................................................. 2-18
2.10.1.3 Two-Sensor Approach .............................................................................................................. 2-18
2.10.1.4 Thermal Mass ........................................................................................................................... 2-18
2.10.1.5 System
Nonlinearity .................................................................................................................. 2-18
2.10.2 Closed Loop PID Control ............................................................................................................. 2-19
2.10.2.1 Proportional (P) ........................................................................................................................ 2-19
2.10.2.2 Integral (I) ................................................................................................................................. 2-19
2.10.2.3 Derivative
(D) ............................................................................................................................ 2-19
2.10.2.4 Manual Output .......................................................................................................................... 2-19
2.10.3
Tuning a Closed Loop PID Controller ........................................................................................... 2-21
2.10.3.1 Setting Heater Range ............................................................................................................... 2-21
2.10.3.2 Tuning Proportional .................................................................................................................. 2-21
2.10.3.3 Tuning Integral .......................................................................................................................... 2-22
2.10.3.4 Tuning Derivative ...................................................................................................................... 2-22
3 INSTALLATION ...................................................................................................................................................... 3-1
3.0 GENERAL ......................................................................................................................................... 3-1
3.1 INSPECTION AND UNPACKING ...................................................................................................... 3-1
3.2 REAR PANEL DEFINITION ............................................................................................................... 3-2
3.3 LINE INPUT ASSEMBLY ................................................................................................................... 3-3
3.3.1 Line Voltage ................................................................................................................................... 3-3
3.3.2 Line Fuse and Fuse Holder ............................................................................................................ 3-3
3.3.3 Power Cord .................................................................................................................................... 3-3
3.3.4 Power Switch ................................................................................................................................. 3-3
3.4 RESISTOR INPUT CONNECTION AND CABLING .......................................................................... 3-4
3.4.1 Resistor Input Connector Definition ................................................................................................ 3-4
3.4.2 Shielding and Twisting ................................................................................................................... 3-4
3.4.3 Driven Guards ................................................................................................................................ 3-5
3.4.4 Isolation and Grounding ................................................................................................................. 3-5
3.4.5 Dressing Cables ............................................................................................................................. 3-6
3.4.6 Temperature Sensors .................................................................................................................... 3-7
3.5
MODEL 3716 SCANNER INSTALLATION ........................................................................................ 3-7
3.5.1 Grounding the Scanner .................................................................................................................. 3-7
3.5.2 Scanner Resistor Input Connector Definition ................................................................................. 3-7
3.5.3 Scanner Resistor Input Cabling...................................................................................................... 3-7
ii Table of Contents