User manual

Section
3: Basic DMM operation Model 2110 5½ Digit Multimeter
Reference Manual
3-38 2110-901-01 Rev. C/August 2013
Autozero
The instrument can correct for drifting by comparing the input signal to zero periodically. You can set
this up to occur automatically or when requested.
To set the instrument to compare to zero automatically, set autozero on. To only compare when
requested, set autozero off.
When the instrument zeroes the input signal, the input signal is measured and then zero is measured.
For the zero measurement, the input signal is internally disconnected and the zero offset is
measured. The instrument then subtracts the zero offset from the signal measurement and displays
the reading:
Displayed reading = Input signal measurement – Zero offset measurement
Zeroing the input signal results in accurate measured readings by canceling out the zero offset.
Autozero is enabled when the instrument is turned on. When it is on, the instrument takes a zero
measurement approximately every two seconds.
Autozero can decrease measurement speed. To increase speed, you can turn autozero off. While this
can increase measurement speed, it will also decrease accuracy over time. If you turn autozero off,
you should use the ZERO:AUTO ONCE command periodically to maintain accuracy.
The instrument takes a single zero measurement in the following situations:
• When you select a different measurement function.
• Any time the instrument processes a ZERO:AUTO command (ON, OFF, or ONCE).
Autozero can be disabled or enabled from the front panel or by using remote operation.
Front-panel operation
Perform the following steps to control autozero:
1. Press the SHIFT and CONFIG (MENU) keys.
2. Use the ◄ and ► keys to display SET ADC and press ENTER.
3. With AUTO ZERO displayed, press ENTER.
4. Use the ◄ or ► key to display ON or OFF and press ENTER.
Remote operation
Use the following command to use autozero:
SENSe:ZERO:AUTO <name> Control autozero
<name> = ON Enable autozero
= OFF Disable autozero
= ONCE Perform autozero once