Voltech AT360, User Manual

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T
ESTS AND
T
EST
C
ONDITIONS
P
AGE
7-30 V
OLTECH
AT
I
U
SER
M
ANUAL
7.1.7 D – D
ISSIPATION
F
ACTOR OR
T
AN
δδδδ
Measurement
Range
Test
Voltage
Test
Frequency
Basic
Accuracy
0.001 to 1000 1mV to 5V 20Hz to 3MHz 0.5%
SEE ALSO THE CAPACITOR TESTING SECTION OF THIS CHAPTER.
The parameter ‘D’ is most often used as a measurement of the losses in a
capacitor. It is analogous to Q for a transformer winding.
For this equivalent circuit the Dissipation Factor D is defined as:
D = Rs (where
ω
ωω
ω
= 2
ππππ
f)
1/
ω ωω ω
Cs
For a given capacitance, the lower the equivalent series resistance, the
lower is the value of the dissipation factor or tan
δδδδ
, i.e. the 'better' the
capacitor.
Where Used
The dissipation factor test would normally be used for capacitors of all types. A
D factor test will help to determine that the capacitor has been manufactured
correctly.
AT Series
Tester
Rs
C