User manual

AC voltage offset
The Model 2000, 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 following 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 negli-
gible. 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 — Measurement Options for information that explain the configuration op-
tions 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 =
2000-900 (J - Aug 2010) BOOK.fm Page 21 Wednesday, October 12, 2011 12:29 PM