B&K Precision 886 - Manual - Manual (Page 21)

18
Charged Capacitors
Always discharge any capacitor prior to making a
measurement since a charged capacitor may seriously damage
the meter.
Effect Of High D on Accuracy
A low D (Dissipation Factor) reading is desirable. Electrolytic
capacitors inherently have a higher dissipation factor due to their
normally high internal leakage characteristics. If the D (Dissipation
Factor) is excessive, the capacitance measurement accuracy may be
degraded.
It is best to check with the component manufacturers’ data sheet to
determine the desirable D value of a good component.
Measuring Capacitance of Cables, Switches or Other Parts
Measuring the capacitance of coaxial cables is very useful in
determining the actual length of the cable. Most manufacturer
specifications list the amount of capacitance per foot of cable and
therefore the length of the cable can be determined by measuring the
capacitance of that cable.
For example: A manufacturers, specification calls out a certain cable,
to have a capacitance of 10 pF per foot, After measuring the cable a
capacitance reading of 1.000 nF is displayed. Dividing 1000pF
(1.000 nF) by 10 pF per foot yields the length of the cable to be
approximately 100 feet.