Self-calibration
The TIVP contains a self-calibration function that corrects Gain Accuracy, DC offset, and frequency response. These
parameters change as the probe warms up to operating temperature and remains constant once the temperature reaches
steady-state. After the probe warms up, self-calibration is recommended when there is a 5°C change in ambient
temperature. An indicator LED on the compensation box provides the status of the self-calibration. See the
on page 27 for more information on the LEDs.
To check the status of the self-calibration programmatically, use the
SELFCAL:STATE? PI
command to determine
whether a self-calibration is
RECOMMENDED
,
RUNNING,
or
PASSED
.
Before performing critical measurements, run a self-calibration to ensure the probe is compensated. It takes about 90
seconds to complete.
Note: The sensor tip cable does not need to be removed from the test point to successfully complete the self-
calibration.
1. Connect probe to an oscilloscope channel.
2. Press the SELF CAL button on the probe compensation box. The Self Cal indicator LED will blink while self-calibration
is in process.
3. Self-calibration is complete when the indicator LED displays green.
To run the self-calibration programmatically, use the
CH<x>:PROBE:SELFCAL EXECUTE PI
command. The
connected channel is specified by "x".
The TIVP probe takes about 20 minutes to warm up. During this time, acquired waveforms may show obvious aberrations.
The following screen shot shows how a 1 KHz square wave appears at the beginning of the warm-up period. Notice how the
probe appears to be uncompensated.
Note: When moving a probe that has fully warmed up to a new oscilloscope channel, you must give the probe
another 5 minutes to warm up on the new channel.
After 20 minutes, most of the aberrations are gone. Self-calibration can be used before the probe reaches its operating
temperature, however those self-calibration settings will become invalid a few minutes later as the internal temperature
changes.
Getting started
TIVP Series IsoVuTM Measurement System User Manual
30
