To get a more accurate number of turns, a coil with a known number of turns is
needed
as a reference. Do the following:
1.
Repeat steps 1 and 2 above with the following changes:
2.
Insert the reference coil into the current probe.
3.
Insert the test coil into the current probe so that the currents are in opposite
directions to each other as shown. The polarity of the coil current must be
observed to determine whether the test coil has more or fewer turns than the
reference coil. The number of turns can be calculated using the following formula:
Application
Reference
N
2
= N
1
x ( I
m
÷
I
1
)
N
2
is the number of turns of the test coil, N
1
is the number of turns of the reference
coil, I
m
is the measurement coil current, and I
1
is the input current.
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