Keithley 2110 User Manual

In this section:
AC voltage measurements and crest factor ............................. 4-1
DMM resistance measurement methods .................................. 4-3
Reference junctions ................................................................. 4-4
Accuracy calculations ............................................................... 4-5
AC voltage measurements and crest factor
The root-mean-square (RMS) value of any periodic voltage or current is equal to the value of the DC
voltage or current which delivers the same power to a resistance as the periodic waveform does.
Crest factor is the ratio of the peak value to the RMS value of a particular waveform. This is
represented by the following equations:
Equation 1: AC voltage measurements and crest factor (1)
The crest factor of various waveforms is different, because the peak-to-RMS ratios are variable. For
example, the crest factor for a pulse waveform is related to the duty cycle; as the duty cycle
decreases, the crest factor increases. The RMS calculations and crest factor (CF) for various
waveforms are shown in the following figures.
Figure 30: RMS calculations and crest factor — sine
Figure 31: RMS calculations and crest factor — half-wave rectified sine
Section 4
Theory of operation

Keithley 2110 Specifications

General

Model	2110
DC Voltage Range	100 mV to 1000 V
AC Voltage Range	100 mV to 750 V
Continuity	Yes
Diode Test	Yes
Category	Digital Multimeter
Display	5.5 digit
DC Current Range	100 µA to 3 A
AC Current Range	100 µA to 3 A
Resistance Range	100 MΩ
Frequency Range	3 Hz to 300 kHz
Frequency Accuracy	0.01% + 1 count
Capacitance Range	1 nF to 100 µF
Capacitance Accuracy	1% + 5 counts
Connectivity	USB, GPIB (optional)
Dimensions	88 mm
Power Supply	100 V to 240 V AC, 50/60 Hz
DC Voltage Accuracy	±0.012% + 2 counts