Technical data

Making Measurements 2
Agilent U1251B/U1252B User’s and Service Guide 39
Measuring Capacitance
The meter measures capacitance by charging the capacitor
with a known current for a period of time, measuring the
voltage and then calculating the capacitance. The larger the
capacitor, the longer is the charging time.
Measuring tips:
• For measuring capacitances greater than 10,000µF,
discharge the capacitor first, then select a suitable
range for the measurement. This will speed up
measuring time in order to obtain the correct
capacitance value.
• For measuring small capacitances, press with
the test leads open to subtract any residual capacitance
from the meter or the leads.
1 Set the rotary switch to .
2 Connect the red and black test leads to the input
terminals and COM respectively.
3 Use the red probe lead on the positive terminal of the
capacitor and use the black probe lead on the negative
terminal.
4 Read the display.
CAUTION
Disconnect the circuit power and discharge all the high-voltage capacitors
before measuring the capacitance to prevent any possible damage to the
meter or the device under test. To confirm that the capacitors have
discharged, use the DC voltage function.
NOTE
means the capacitor is charging. means the capacitor is
discharging.