I found this set of vintage Phywe inductors at a yard sale and thought they might be fun to play with.
They are marked 300 (4A), 600 (2A), 1200 (1A), and 12000 (0.05A).
I assume the "A" figures are current ratings, but I can't figure the other numbers.
All these are approx the same size and shape, 1.25" diameter coil form about 2.5" long.
Using this webpage to estimate the inductance:
http://www.dos4ever.com/inductor/inductor.html
And the values don't come close to the coil markings. Here are the figures I measure:
300 (4A) coil- 2.3mH (2300uH), DC resistance = 0.65 ohms
600 (2A) coil- 8.9mH (8891uH), DC resistance = 2.3 ohms
1200 (1A) coil- 30mH (30,000uH), DC resistance = 11.5 ohms
12000 (0.05A) can't measure, DC resistance = 1430 ohms
Working backwards using formulas, speculating the markings might refer to the number of windings, the figures I get don't correspond.
So what is your guess to what the markings are referring to? Am I simply using the wrong method of estimating?
I wonder if the square openings were designed to insert iron or other core materials?
Thanks,
Keith Ostertag
They are marked 300 (4A), 600 (2A), 1200 (1A), and 12000 (0.05A).
I assume the "A" figures are current ratings, but I can't figure the other numbers.
All these are approx the same size and shape, 1.25" diameter coil form about 2.5" long.
Using this webpage to estimate the inductance:
http://www.dos4ever.com/inductor/inductor.html
And the values don't come close to the coil markings. Here are the figures I measure:
300 (4A) coil- 2.3mH (2300uH), DC resistance = 0.65 ohms
600 (2A) coil- 8.9mH (8891uH), DC resistance = 2.3 ohms
1200 (1A) coil- 30mH (30,000uH), DC resistance = 11.5 ohms
12000 (0.05A) can't measure, DC resistance = 1430 ohms
Working backwards using formulas, speculating the markings might refer to the number of windings, the figures I get don't correspond.
So what is your guess to what the markings are referring to? Am I simply using the wrong method of estimating?
I wonder if the square openings were designed to insert iron or other core materials?
Thanks,
Keith Ostertag