- Joined
- Jul 11, 2005
- Messages
- 129
Hi all, it happened again. In my journey of trying to do transformers myself, I stumbled on another strange measurement I did today.
I wound 2 nearly identical transformers but I got strangely different measurement results.
So both transformers are wound on the same nickel50 UU core, 2 bobbins each containing 1/2 pri and 1/2 sec. 1:1 - 1000 windings per coil. both pri. and sec. coils connected in reverse.
When I measure inductance with my LCR meter (@100Hz), one transformers coils measure ~8,5H, the other ones coils measure ~0.85H. only a tenth of the other.
the only difference is a copperfoil shield layer between pri. and sec. on the transformer with the lower inductance measurement.
HOW? Can anyone explain me the measurement?
at first I thought there was an error in the coil or measurement, but all of them measure the same.
frequency response is nearly the same on both transformers.
thank you very much!
I wound 2 nearly identical transformers but I got strangely different measurement results.
So both transformers are wound on the same nickel50 UU core, 2 bobbins each containing 1/2 pri and 1/2 sec. 1:1 - 1000 windings per coil. both pri. and sec. coils connected in reverse.
When I measure inductance with my LCR meter (@100Hz), one transformers coils measure ~8,5H, the other ones coils measure ~0.85H. only a tenth of the other.
the only difference is a copperfoil shield layer between pri. and sec. on the transformer with the lower inductance measurement.
HOW? Can anyone explain me the measurement?
at first I thought there was an error in the coil or measurement, but all of them measure the same.
frequency response is nearly the same on both transformers.
thank you very much!
