Appendix
EN
Copyright © Qingdao Hantek Electronic Co., LTD
HBT3000 series user manual
65
11.3
Appendix C: Performing Zero Adjustment
To remove residual components caused by bias voltage or measurement
environment of this instrument, please perform zero adjustment before
measurement, and the testing accuracy will be specified after zero adjustment.
Zero adjustment refers to the function of subtracting the residual value when
measuring 0 to adjust the zero point, so it is necessary to perform zero
adjustment when connected to 0. Considering that it is unrealistic to connect the
test object without resistance in reality. So, in the actual zeroing process, zeroing
is achieved by establishing a state close to 0. If zero adjustment is not performed
correctly, the correct measurement value cannot be obtained.
11.3.1
Zero adjustment wiring principle
According to Ohm's law E=I * R, in order to establish a state close to 0, it is
necessary to short-circuit directly between SENSE-H (red) and SENSE-L (black).
The voltage between SENSE-H and SENSE-L is approximately 0V, and the specific
calculation is as follows:
Figure 11-2 Zero adjustment schematic diagram
RSEH and RSEL are wiring resistors for SENSE-H and SENSE-L
RSOH and RSOL are the wiring resistors for Source-H and Source-L
RShort is the short-circuit resistance
I0 is the current flowing from SENSE-H to SENSE-L
I is the current flowing from Source-H to Source-L
Then:
E=(I
0
×
R
SEL
)+(I
0
×
R
SEH
)
