GW Instek GDM-8261 User Manual - Manual (Page 87)

SYSTEM/DISPLAY CONFIGURATION
87
3. Press the Down key. The input
current detect setting appears.
1st display Shows the current detect setting
4. Select the setting using the
Up/Down keys.
5. Press the Enter key to confirm
your selection. Press the Exit
key to go back to the default
display.
AUTO
ENTER
/ EXIT SHIFT
ADC Setting
Auto-Zeroing
Background The Auto Zeroing (A-Zero) function can be used in
resistance, TC, RTD, DCV and DCI measurements.
Auto zeroing is used to prevent measurements from
drifting by taking offset measurements.
Setting Off, On (default=On)
Theory The combined offset from the input buffer, A/D driver
and ADC is called the total offset. Due to temperature
variations inside the GDM-8261, the offsets for the
Buffer, A/D driver and ADC vary over time, and thus
the total offset will also vary over time.
Auto Zero deducts this total offset from the measured
signal to obtain a more accurate reading. If Auto Zero is
turned off, this total offset will not be deducted from the
measured signal.
Auto zero works in the following manner:
Internally, the DMM will periodically short the Buffer’s
Hi and Lo input to obtain a total offset. The frequency at
which the offset is obtained depends on the sample rate.