Now you're into an activist program. I like it!
Next we find the software engineer that wrote the AI program for constructing unanswerable questions.

 

"The filter caps, bridge rectifier or regulator don't can't if the line frequency is 60hz or 400hz or 800hz"

This is not true, and is the source of the potential problems.

For linear power supplies and typical control transformers that are rated for both 50 Hz and 60Hz, usually the datasheets indicate that the power or current ratings are different for the two input frequencies. This is because the impedance of the primary and secondary windings change with frequency, something true of all inductors. Also, the transformer core material has an impedance to magnetic flux, and the steel used in 50/60 Hz transformers overheats at 400 Hz. 400 Hz transformers use a different core alloy or material.

Also, diodes that work fine at 50/60 might overheat at 400/800 because they are taking too long to turn on and off. All diodes have junction capacitance and other device physics properties that make them appropriate or not appropriate for certain frequency ranges. Finally, the ripple current in the filter capacitors increases with frequency, which can cause overheating and premature failure.

Switching power supplies can be more forgiving if properly designed, because the power transformer does not see the input line frequency, only the primary side switching frequency. So if the input diodes and capacitors are designed for 400 Hz operation, the supply usually is rated for 50/60/400 Hz operation.

ak

 

The only thing really off the wall about the original post was the assertion (hypothesis) that the line frequency was being changed in some fashion. I think the implication was that we were talking about AC-AC power conversion. I could be wrong though -- it has happened before.

 

Some AC power supplies have a built in oscillator that can change the Line frequency to 60hz, 120hz, 400hz, 800hz. Can I power a circuit board that is designed for 60hz and power it up with 400hz or 800hz or power a circuit board that is designed for 115 at 400hz and use a regular power supply at 115 vac at 60hz? What would I have change in the design to power a circuit board that is designed for 115vac at 400hz to work with a power supply that is 115vac at 60hz? is there any problems or it will work?

If the equipment has a mains transformer - that has reactance that presents a particular impedance at 60Hz, higher frequency will increase the impedance and reduce the current draw - it may not pass enough power to the load for correct operation. A higher frequency will also induce more eddy currents in the core laminations - they may get hot!

Anything with a bridge rectifier/reservoir will work from DC up - but no one uses fast diodes in mains bridge rectifiers.

Most PFC front ends are basically flyback boost converters with no mains side reservoir capacitor, they draw pulses from the raw rectifier whose current amplitude more or less tracks the AC waveform - a higher 'mains' frequency would allow less of the pulses per half-cycle, it'd probably work but i've never tried it.

 

No the circuit boards under test don't have a power supply, the power supply circuit is disconnected or it needs an external power supply 115vac at 400hz

I don't own an AC power supply 115vac at 400hz.

That is why I am asking If i power up these circuit boards using a AC power supply at 115vac at 60hz what will happen.

The circuit boards don't have a power supply board. But they use an external power supply that is 115vac at 400hz

If I use an external power supply at 115vac at 60hz to power up these circuit boards what will happen?

 

The boards don't have a power supply. Do they have DC inputs that are provided by the external power supply that is 115vac at 400hz?

 

No the circuit boards under test don't have a power supply, the power supply circuit is disconnected or it needs an external power supply 115vac at 400hz

I don't own an AC power supply 115vac at 400hz.

That is why I am asking If i power up these circuit boards using a AC power supply at 115vac at 60hz what will happen.

The circuit boards don't have a power supply board. But they use an external power supply that is 115vac at 400hz

If I use an external power supply at 115vac at 60hz to power up these circuit boards what will happen?

If you have devices designed to run off a PSU - plugging them into 115V 60Hz will result in a fairly loud bang.

You might want to wear safety glasses while you're at it too!

 

The boards don't have a power supply. Do they have DC inputs that are provided by the external power supply that is 115vac at 400hz?

The DC gets converted by the circuit. It converts 115VAC at 400hz into DC voltages

The circuit boards don't have a line transformer that is why you use an external power supply 115vac at 400hz

The circuit boards run off an AC 115 vac 400hz not a DC power supply

The Elgar model 201 External powers supply plugs into a wall socket at 120vac at 60hz and converts the line frequency into 400hz from an oscillator board built into the ELGAR power supply. It's an AC to AC power supply. Not an AC to DC power supply. There is no DC output on ELGAR power supplys.

The circuit boards under test gets supplied by an Elgar AC to AC power supply. The only difference is the line frequency.

My question is does the line frequency really matter to a circuit board or does the circuit board really care what the line frequency is to operate?

I can't find in any of my electronic books about if the line frequency matters or not to a circuit board.

example would be if i bypass the power supply section in my home radio amplifier or guitar amp and used an external powers supply at 115vac at 400hz instead of at 60hz would my guitar amplifier work or cause noises and oscillators from the 400hz ripple going through the power rails or would it make no difference?

 

To Bypass the Line transformer in a home radio amplifier or guitar amplifier or any circuit board that needs to be powered using AC 115vac at 60hz

 

The DC gets converted by the circuit. It converts 115VAC at 400hz into DC voltages

That, to me, is a power supply on the board. If designed for 400hz, the filters will probably not do a good job at 60hz. (I think this has already been stated earlier.)

 

So the only difference is the filter cap values?

Is there a difference between a 60hz bridge rectifier and a 400hz bridge rectifier because of the type of diodes used?

 

NO

 

YES.

 

what are the differences please?

 

Wow its been a long time since I saw a thread with so much misinformation about basic power supply components and how they work together in a simple circuit.

 

RTFM

read the fine manual

 

Wow its been a long time since I saw a thread with so much misinformation about basic power supply components and how they work together in a simple circuit.

Such as...?

 

Such as...?

Such as lumping a bunch of unspecified circuit boards into a single line of questioning, each needing a different frequency from DC to 800 Hz, and repeatedly asking for one answer to fit all the boards.

 

Actually, I was asking about the basic power supply components. If I'm missing something, I'd like to know.

 

Shorter answer.

Common power diodes and capacitors typically work just fine at frequencies under at least a few KHZ. I have never seen any modern day devices made that had such poor ratings as to only be good for 50 - 60 Hz operation.

Common iron core transformers rarely have core overheating issues from running above their designed frequency. In practical application they usually have problems with passing enough power at higher frequencies to be able to overheat due to the their primary winding impedance becoming a dominant power/current limiter as frequency goes up just as it does in an iron core type inductor or choke.

As capacitors go I am not aware of any electronics that when used in DC power supply ripple filtering develop over current issues as the supply ripple frequency goes up. Natural internal ESR and impedance tends to limit what they can carry making their internal losses lower as the frequency goes up because they can not charge or discharge fast enough.
Think of it like using electrolytic capacitors in an audio amplifier for a output stage or crossover network. Putting higher frequencies through them has little effects until ESR or impedance characteristics come into play and even then those tend to reduce the amount of power they are handling.

Granted in special cases these things may happen but for the most part in typical power supplies made from at least half assed quality parts operating under a few KHz input frequency powering a predetermined DC load its not likely to be an issue.