is this at Mains voltage? or at low isolated voltage?
The relay is doing more than just bypassing the limiting resistors.
It is connecting power through the N.C. contact.
It disconnects power during change over.
It connects power through the N.O. contact direct to mains after change over and crucially AFTER a short "no current period".
I consider this a bad way to wire in a Mains relay.
The "timer" section has a delay time that is very variable.
At high mains voltage the relay triggers fairly quickly and draws lots of coil current leading to risk of overheating.
At low mains voltage the relay triggers after a much longer delay and in some cases does not trigger at all. This leaves the limiting resistors in circuit.
An RC circuit used as a timer for a relay coil is a very bad way to implement a timer and massively increases the risk of failure.
However, iRC timing is adopted by many Builders.
I can't understand why they think the risks are acceptable.
The relay is doing more than just bypassing the limiting resistors.
It is connecting power through the N.C. contact.
It disconnects power during change over.
It connects power through the N.O. contact direct to mains after change over and crucially AFTER a short "no current period".
I consider this a bad way to wire in a Mains relay.
The "timer" section has a delay time that is very variable.
At high mains voltage the relay triggers fairly quickly and draws lots of coil current leading to risk of overheating.
At low mains voltage the relay triggers after a much longer delay and in some cases does not trigger at all. This leaves the limiting resistors in circuit.
An RC circuit used as a timer for a relay coil is a very bad way to implement a timer and massively increases the risk of failure.
However, iRC timing is adopted by many Builders.
I can't understand why they think the risks are acceptable.
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Because they looking for solutions for problems that not exist.
It is a resolution theorem THROUGH same solution, in this case the absurd's theorem. They love to find solutions to problems that do not exist and therefore start the problems and then fix them. Rather than look for simple solutions.
It is a kind of nerd thought.
However, the solution is clear to some, and there are not many options above, the problems are not the inrush and many more, is not it?
Then why not he stop bothering spinning with so many options and some enlightened comes up with a circuit that can be extrapolated to any problem.
It is a resolution theorem THROUGH same solution, in this case the absurd's theorem. They love to find solutions to problems that do not exist and therefore start the problems and then fix them. Rather than look for simple solutions.
It is a kind of nerd thought.
However, the solution is clear to some, and there are not many options above, the problems are not the inrush and many more, is not it?
Then why not he stop bothering spinning with so many options and some enlightened comes up with a circuit that can be extrapolated to any problem.
finally i have decided to use 10ohm 50W ceramic resistor at the primary to handle the initial current and the trigger circuit is a generic Schmidt trigger circuit. I have a question that how much psu cap per rail do you recommend for a duration of 1sec. I have plans to use upto 2,00,000uF per rail.
I have one question for you: why did you choose 2F? Why stop there? If 2F is good what about 22F? 220F? Do you get what I am after here? How do you justify, and what benefit do you expect, from using these levels of capacitance in your PS?
I think OP is repeatedly making a typo, either by including the comma or omitting a zero. In the title of the thread, the missing zero appears, but in a later post OP says 0.1F but should go up to 1F!
I am sensing that the OP doesn't really know what a linear PS needs to do and what it doesn't need to do, and is rather liberally over applying the "more is more" principle...
Haven't you heard of inductors?
As Walt very politely points out (eight pages in), this is, basically, a silly idea.
If you really want an inrush current limiter there's a thing called "an inductor".
Once upon a time designers knew what these were and how to design power supplies with them.
People even made special power supply chokes with current controlled inductance ("swinging chokes") to make design easier.
Strangely enough, choke input power supplies have better regulation than capacitor input power supplies (the reason usually stated for obscenely large capacitor banks)
For those who can't (or won't) do the math there's spice and psud
As Walt very politely points out (eight pages in), this is, basically, a silly idea.
If you really want an inrush current limiter there's a thing called "an inductor".
Once upon a time designers knew what these were and how to design power supplies with them.
People even made special power supply chokes with current controlled inductance ("swinging chokes") to make design easier.
Strangely enough, choke input power supplies have better regulation than capacitor input power supplies (the reason usually stated for obscenely large capacitor banks)
For those who can't (or won't) do the math there's spice and psud
Why do you KEEP typing that stupid nonsense?
THAT IS NOT A NUMBER IN ENGLISH.
You've been told so many times, yet you insist or couldn't care less.
If you want answers, first learn to write.
Agreed...............If you want answers, first learn to write.
Then learn to formulate the question so that we can understand what is required.
I really didnt understand what you are saying im sorry infact 1F = 1000000 microfarad as listed in this website.. F to uF Converter, Chart -- EndMemo
what is wrong in that?
what is wrong in that?
well I require 40A for a duration of 100ms well now how much should be my supply cap?
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