now we know what you are trying to measure to, tell us what the probe to probe resistance reading and also the probe vias winding to probe resistance reading is.
That way we and you can compare the extra resistance as the likely winding resistance.
<=0r1 indicates a big fat secondary capable of many amperes.
1r0 indicates a big fat primary capable of many hundreds of VA.
10r starts to show current limitations.
That way we and you can compare the extra resistance as the likely winding resistance.
<=0r1 indicates a big fat secondary capable of many amperes.
1r0 indicates a big fat primary capable of many hundreds of VA.
10r starts to show current limitations.
I get almost no resistance on each group of windings.
The resistances should be extremely low given the currents involved when this transformer is being used in its intended application.. This is largely a way to identify which wires are associated with a specific winding. Once you know this you can apply power as described in my previous post and determine the winding voltages.
Just be careful!
GROUP ON LEFT #1
BK+OR= .5
BK+WT= 1.3
OR+WT= 1.2
TOP GROUP ON RIGHT #2
WT+RD= .5
WT+BK= .5
RD+BK= .5
LOWER GROUP ON RIGHT #3
RD+BK= 0
RD+BR1= 0
RD+BR2= 0
BR1+BR2= 4.3
BK+BR1= 2.4
BK+BR2= 2.4
---------------------------------------------------------------------------------------------------------------------------
RD#2+RD#3= .4
WT#2+RD#3= .5
BK#2+RD#3= .5
BK+OR= .5
BK+WT= 1.3
OR+WT= 1.2
TOP GROUP ON RIGHT #2
WT+RD= .5
WT+BK= .5
RD+BK= .5
LOWER GROUP ON RIGHT #3
RD+BK= 0
RD+BR1= 0
RD+BR2= 0
BR1+BR2= 4.3
BK+BR1= 2.4
BK+BR2= 2.4
---------------------------------------------------------------------------------------------------------------------------
RD#2+RD#3= .4
WT#2+RD#3= .5
BK#2+RD#3= .5
this confirms that the whole is a single winding.
The resistances indicate similar turns in both halves.
It is safe to assume this is a centre tapped winding. You can test the voltages later.
Does your meter read ~0r3, when checked probe to probe?
Have you subtracted that probe to probe reading from the reading when you measured the windings?
eg 2r4 - 0r4 = 2r for both half windings
4r3 - 0r4 = 3r9 for the total series winding. The error is <= 2.5% That's surprisingly good, for readings right down near least significant digit.
How consistent is the probe to probe reading?
Is it always 0r4, for ten readings in succession, after 1 to 3 seconds to allow the meter reading to stabilise?
eg 2r4 - 0r4 = 2r for both half windings
4r3 - 0r4 = 3r9 for the total series winding. The error is <= 2.5% That's surprisingly good, for readings right down near least significant digit.
How consistent is the probe to probe reading?
Is it always 0r4, for ten readings in succession, after 1 to 3 seconds to allow the meter reading to stabilise?
Now go back and adjust out the current offset that your DMM reads from the measurements you have taken.
If your meter offset is 0r4 then you can't have read 0r0.
Do you mean off top of scale? i.e. more than 199r9?
Be sure you understand what your instruments are telling you !!!
What do these mean?
If your meter offset is 0r4 then you can't have read 0r0.
Do you mean off top of scale? i.e. more than 199r9?
Be sure you understand what your instruments are telling you !!!
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