IET Labs, Inc. 1864-1644, User And Service Manual

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CONTENTS, FIGURES, AND TABLES
1864-1644 Positive Polarity Megohmmeter
iii
Figures
1864-1644 Front-panel Controls, Connectors and Indicators ................................. iv
Figure 1-1. Type 1864-1644 Front-panel Controls, Connectors and Indicators ..... 2
Figure 1-2. Type 1864-1644 rear-panel controls and connectors .......................... 4
Figure 1-3. Methods of connection to the measurement terminals ........................ 5
Figure 2-1. Dimensions of the GR/IET 1864-1644 Megohmmeters ...................... 7
Figure 3-1 Ground-link connection to GUARD and to -UNKNOWN terminals ... 9
Figure 4-1. Electrode arrangement for resisitivity measurements ......................... 14
Figure 4.2 Basic megohmmeter circuit ................................................................... 15
Figure 4-3. Guarded measurement of a three-terminal resistor .............................. 16
Figure 5-1 Megohmmeter block diagram ............................................................... 20
Figure 6-1. Connections for measuring standard resistors ..................................... 22
Figure 6-2. Top interior view of 1864 Megohmmeter ........................................... 26
Figure 6-3. Bottom interior view of 1864 Megohmmeter ...................................... 26
Figure 7-1. Replaceable mechanical parts on the 1864-1644 ................................. 31
Figure 7-3. Type 1864 recti fi er circuit etched-board assembly .............................. 32
Figure 7-2. Regulator and ampli fi er circuits etched-board assembly ..................... 32
Figure 7-4 Type 1864 switching diagram ............................................................... 33
Figure 7-5. Type 1864 schematic diagram .............................................................. 34
Figure 7-6. Complete cabinet assembly .................................................................. 35