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Circuit breaker - which to choose

I install a replacement electric cooktop in the kitchen. It's rated for a 30A breaker for all 7 burners running on high ALL AT ONCE. I only have a 20A circuit. I ask the installer what to do explaining our use case. We only use one to a maximum of three of the seven burners at a time and usually with a 5 setting not 9. He says if that's the case it will work fine but if you start using 5 burners at once the circuit breaker could trip. It's been in the house 7 years now and the circuit never tripped.

It's much the same with sound systems. People look at the max wattage quoted for amps and add them all up thinking that's what they need for power. In reality, users will never use even 40% of the total and never trip a breaker. If a breaker does trip it's likely a short in the equipment rather than amps needing more power than a 15A circuit can provide. In that case, I actually want a more sensitive breaker. The pain from extremely loud environment usually kicks in before a breaker trip.
 
there is no possibility that a single amplifier can pull 15A on any curve upon startup unless it is faulty.
Check inrush current they said in torroidial transformers it might be 60 times...
 
If breaker rates at 80% then 16 amp will sustain 12.8 amp and class D trip curve will hold till over 10 times at 128 amps. If your amplifier trips a breaker that can accommodate inrush of minimum 128 amps then I would look at the amplifier not the breaker.
Uhm confused.
I don't have cb with D curve. So I don't know if it trips such a cb.
 
First get that amp checked out so that you know it is not drawing excess current on power ON.
The problem is it's 15kg box and I don't have service company in my country...

Repace current cb with a which one?
We were discussing curves not power....
 
In that case, I actually want a more sensitive breaker. The pain from extremely loud environment usually kicks in before a breaker trip.
Don't get it
By more sensitive breaker you mean?

What's extremely loud environment?
It trips cb on powering on not whille playing...

No idea what are these shorts in equipment.
 
Also which I don't get...
Is how can short occurs randomly...
If there is a short it will happen all the time I believe...
 
Check inrush current they said in torroidial transformers it might be 60 times...
As mentioned earlier, the theoretical instantaneous value of current draw according to inductor complex numbers calculations indicate infinite current limited by only the source resistance for maybe a very small tiny fraction of a second. The other seconds of the draw is very manageable. BUT that does not mean you need snake oil CBs... So that can be calculated but it's really a very tiny small amount of time in which it occurs and it's all around us and stuff functions very well with that. So don't sweat it or the other few percent of the time that the current draw is pretty large. Even if 60 times that's way less than theoretical calculations so don't sweat stuff OK. :D
 
The problem is it's 15kg box and I don't have service company in my country...
I've handled electrical stuff with 20T overhead cranes building oil and gas heavy machinery... 15 kg is peanuts...LoL. Don't sweat it...
 
Contact an licensed electrician they can dimension the fuse/CB for you .

They can pick a characteristics for example a fuse/CB suitable for motor start that's more " slow blow " but upping from 10A to 16A and only have the hifi on this fuse is going to do a lot anyway so almost anything would do.

I real electrician can check what's up to code in your area and what the wiring can stand.

And selectivity ,you not to pick a fuse/CB that's so slow that another CB "higher up" in the circuit trips instead . It can not be bigger than the one feeding your home as an obvious example .

Amps like this really needs a soft start circuit ? weird that its not included ,if the amp is not broken.
A better solution for your problem if the amps is not broken would be a softstart circuit in the amp ?
 
@roxor I think we need to re-start this whole process again. It's getting diverted from reality and we are better than that. Set your goal(s) and we can proceed accordingly but not change the terms while we are doing that. You are expected to be able to manage stuff on your end of the deal. 15 kg was bit of a woosy silly complaint even if shipping it around a continent. I've almost died fighting a ~127kg pesky persistent enemy that I eventually managed to defeat and you are complaining about a 15 kg box... sigh* It's rather silly... Can we work together now? I'm trying my best to help here. Be realistic, responsible and we can work together.
 
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I've handled electrical stuff with 20T overhead cranes building oil and gas heavy machinery... 15 kg is peanuts...LoL. Don't sweat it...
i dont understand your comments at all sorry.
 
Contact an licensed electrician they can dimension the fuse/CB for you .
just not sure why some electrician should know to dimense fuse/CB for the specific amp ...

i have feeling we are circling here ... w/out action steps...
 
The inrush current is variable it depends on where on the sinus wave you happen to turn on the amp .

It's AC voltage so if you lucky the voltage is 0 when turning on and the start gets softer if your unlucky the voltage is at peak positive or negative -+sqrt(2)*230V
 
Contact an licensed electrician they can dimension the fuse/CB for you .

They can pick a characteristics for example a fuse/CB suitable for motor start that's more " slow blow " but upping from 10A to 16A and only have the hifi on this fuse is going to do a lot anyway so almost anything would do.

I real electrician can check what's up to code in your area and what the wiring can stand.

And selectivity ,you not to pick a fuse/CB that's so slow that another CB "higher up" in the circuit trips instead . It can not be bigger than the one feeding your home as an obvious example .

Amps like this really needs a soft start circuit ? weird that its not included ,if the amp is not broken.
A better solution for your problem if the amps is not broken would be a softstart circuit in the amp ?
the amp is
PSU box just transformers
and soft start ie capacitors etc happening inside the AMP box, and i think the soft start is there..

but PSU box is just to power on transformers immediately w/out any delay.
 
just not sure why some electrician should know to dimense fuse/CB for the specific amp ...

i have feeling we are circling here ... w/out action steps...
it does not need to be specific it's should just not blow when you start , don't overthink this
 
the amp is
PSU box just transformers
and soft start ie capacitors etc happening inside the AMP box, and i think the soft start is there..

but PSU box is just to power on transformers immediately w/out any delay.
You would think the designers of really powerful amps would think about adding softstart circuits in their products :)
 
It's AC voltage so if you lucky the voltage is 0 when turning on and the start gets softer if your unlucky the voltage is at peak positive or negative -+sqrt(2)*230V
but if u are not lucky ... how does that affect Inrush current?
 
I don't know, currently
My MF nu Vista m3 is sometimes randomly tripping 10a and also 16a cb...

So I was told that apart of ampers there are different curves per cb... For inrush current.
OK -0 lets simplify.


You need to install a circuit with enough current capacity for your equipment. This will be lower than you think. Even if your amp is 500W per channel, you will need (at most) 2KW capability in your circuit (assuming you don't have any other high power devices) - so that would only need about 9A for that. In reality it will be much less. You are unlikely ever to be putting more than about 20W average into your speakers, so in reality will be typically using less than 100 to 200W for the complete audio system. (Add more if you are powering PC's, monitors, tvs etc)

So - as you can see a 16A breaker will be more than enough.

You suggested 2.5mm cable. In the UK this can be used for circuits protected by a 32A breaker - so again, plenty of headroom.

The type of breaker you use is specified by your local wiring regulations, and has nothing to do with the type of equipment you are powering.

See this link for inormation on UK regs.

You will need similar info but specific to your location.
 
Has your amplifier only recently tripped the breaker? Has the breaker been replaced?

If this is relatively new, it's either the amplifier PSU developing a fault or the breaker needs replacing.
 
@antcollinet then i have no clue why that PSU of the AMP is tripping CB even no other devices are on the circle...
and it occurs randomly so i believe there are no shorts... as everything works fine once the PSU is powered on and CB is not tripped.
 
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