If a CT originally designed to be applied at 50 Hz circuit is installed at 60Hz which would be the influence over the secondary saturation voltage? Thanks Skogsgurra (Electrical)9 Dec 14 10:57 The saturation voltage increases 20% The reason is that the sine's half-period is only 8.33 ms at 60 Hz, while it is 10 ms at 50 Hz and that saturation is dependent on volt-seconds absorbed. With narrower sine, you can have more volts. Gunnar Englund www.gke.org -------------------------------------- Half full - Half empty? I don't mind. It's what in it that counts. electrolitic (Electrical) (OP) 9 Dec 14 11:27 Thanks Skogsgurra I had thought the same but I was concerned with the "B" ( the magnetic flux density in Tesla) that also depends of frequency (number of turns/core cross section of course are the same). Why my concern doesn't make sense? Thank you again. electricpete (Electrical)9 Dec 14 13:07 Gunnar was certainly right. To say it another way: Let’s say you are doing a simple secondary excitation test. You are applying voltage to an iron-core inductor. Now decrease the frequency of the test voltage (without the voltage magnitude) . What happens? f = Frequency decreases The impedance of inductor X = j*2*pi*f*L decreases. The excitation current I = V / X increases. The flux density B = N*I / [Reluctance*A] increases. The core is further towards saturation.

If a CT Originally Designed to Be Applied at 50 Hz Circuit is Installed at 60Hz Which Would Be the Influence Over the Secondary Saturation Voltage

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CT Originally Designed to Be Applied at 50 Hz Circuit is Installed at 60Hz Which Would Be the Influence Over the Secondary Saturation Voltage

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Page 1: If a CT Originally Designed to Be Applied at 50 Hz Circuit is Installed at 60Hz Which Would Be the Influence Over the Secondary Saturation Voltage

The reason is that the sine's half-period is only 8.33 ms at 60 Hz, while it is 10 ms at 50 Hz and that saturation is dependent on volt-seconds absorbed. With narrower sine, you can have more volts.

Gunnar Englundwww.gke.org--------------------------------------Half full - Half empty? I don't mind. It's what in it that counts.

electrolitic (Electrical)(OP)9 Dec 14 11:27Thanks SkogsgurraI had thought the same but I was concerned with the "B" ( the magnetic flux density in Tesla) that also depends of frequency (number of turns/core cross section of course are the same). Why my concern doesn't make sense? Thank you again.electricpete (Electrical)9 Dec 14 13:07Gunnar was certainly right.

To say it another way: Let’s say you are doing a simple secondary excitation test. You are applying voltage to an iron-core inductor. Now decrease the frequency of the test voltage (without the voltage magnitude) . What happens?

f = Frequency decreasesThe impedance of inductor X = j*2*pi*f*L decreases.The excitation current I = V / X increases.The flux density B = N*I / [Reluctance*A] increases. The core is further towards saturation.