2-wire functions ................................................................................. 2-8
4-wire functions (paired channels) .................................................... 2-8
Controlling the system channel ......................................................... 2-9
Non-amp and non-measure switching modules .............................. 2-13
Multiple channel operation ..................................................................... 2-15
Controlling multiple channels ......................................................... 2-17
Multiple channel operation anomalies ............................................ 2-21
Dual independent multiplexers ........................................................ 2-23
Identifying installed modules and viewing closed channels .................. 2-28
CARD menu .................................................................................... 2-28
Switching module queries (remote operation) ................................ 2-30
Relay closure count ................................................................................ 2-32
Reading relay closure count ............................................................ 2-33
Setting count update interval ........................................................... 2-33
Model 7700 switching module ............................................................... 2-34
Switching module capabilities ........................................................ 2-34
Schematic diagram .......................................................................... 2-35
3 Basic DMM Operation
DMM measurement capabilities ............................................................... 3-2
High energy circuit safety precautions ..................................................... 3-3
Performance considerations ...................................................................... 3-4
Warm-up ............................................................................................ 3-4
Autozero ............................................................................................ 3-4
LSYNC (line cycle synchronization) ................................................ 3-5
Remote programming — autozero and LSYNC ............................... 3-6
Channel list parameter (<clist>) ............................................................... 3-7
Voltage measurements (DCV and ACV) .................................................. 3-8
DCV input divider ............................................................................. 3-8
Connections ....................................................................................... 3-8
Volts measurement procedure ......................................................... 3-11
Crest factor ...................................................................................... 3-12
Low level considerations ................................................................. 3-12
Current measurements (DCI and ACI) ................................................... 3-14
Connections ..................................................................................... 3-14
Amps measurement procedure ........................................................ 3-15
AMPS fuse replacement (front panel AMPS input) ........................ 3-16
Resistance measurements (Ω2 and Ω4) .................................................. 3-16
Connections ..................................................................................... 3-17
Standard resistance measurements .................................................. 3-19
Offset-compensated ohms ............................................................... 3-20
Dry circuit ohms (DRYCKT) .......................................................... 3-22
Temperature measurements .................................................................... 3-25
Thermocouples ................................................................................ 3-25
2750-900-01.book Page 2 Wednesday, August 3, 2011 7:56 AM