Keithley 3730 User Manual

Section
5: Basic Digital Multimeter (DMM) Operation Series 3700 System Switch/Multimeter
User's Manual
5
-4 Document Number: 3700S-900-
01 Rev. A / August 2007
Line cycle synchronization
Synchronizing A/D conversions with the frequency of the power line increases common mode
and normal mode noise rejection. When line cycle synchronization is enabled, the measurement
is initiated at the first positive-going zero crossing of the power line cycle after the trigger.
The following figure shows a measurement process that consists of two A/D conversions. If the
trigger occurs during the positive cycle of the power line (Trigger #1), the A/D conversion starts
with the positive-going zero crossing of the power line cycle. If the next trigger (Trigger #2)
occurs during the negative cycle, then the measurement process also starts with the
positive-going zero crossing.
NOTE Line synchronization is not available for the AC functions (ACV, ACI, FREQ, or
PERIOD). Line synchronization can be enabled for  1.0PLC measurement,
increasing NMRR and CMRR.
See dmm.linesync contained in the reference manual for remote programming information.
Figure 5-1: Line cycle synchronization
Voltage measurements (DCV and ACV)
The Series 3700 can make DCV measurements from 0.01μV to 300V and ACV measurements
from 0.1μV to 300V RMS (425V peak for AC waveforms).
 DCV input resistance: 100mV through 10V ranges: >10GΩ
 100V and 300V ranges: 10MΩ
Refer to the specifications for complete and updated information and tolerances.

Keithley 3730 Specifications

General

Brand	Keithley
Model	3730
Category	Multimeter
Language	English