Keithley 2010 User Manual

AC voltage offset
The Model 2010, at 5½ digits resolution, will typically display 100 counts of offset on AC
volts with the input shorted. This offset is caused by the offset of the TRMS converter. This offset
will not affect reading accuracy and should not be zeroed out using the REL feature. The follow-
ing equation expresses how this offset (V
OFFSET
) is added to the signal input (V
IN
):
Example: Range = 1VAC
Offset = 100 counts (1.0mV)
Input = 100mV RMS
The offset is seen as the last digit, which is not displayed. Therefore, the offset is negligible.
If the REL feature were used to zero the display, the 100 counts of offset would be subtracted
from V
IN
, resulting in an error of 100 counts in the displayed reading.
See Section 3 for information on the configuration options for DC and AC voltage
measurements.
Displayed reading V
IN
()
2
V
OFFSET
()
2
+=
Displayed reading 100mV()
2
1.0mV()
2
+=
Displayed reading 0.01V()110
6–
V×()+=
Displayed reading 0.100005 =
Basic Measurements 2-19

Keithley 2010 Specifications

General

Frequency Range	3 Hz to 300 kHz
DC Voltage Range	100 mV to 1000 V
AC Voltage Range	100 mV to 750 V
DC Current Range	3 A
DC Current Accuracy	0.05%
AC Current Range	3 A
Resistance Accuracy	0.01%
Interface	GPIB, RS-232
Power Supply	50 Hz or 60 Hz