Do new houses have weaker breakers?

  • Thread starter cameron paterson
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H

Hobbit

Audioholic Chief
Believe it! Powerful amps blow breakers. My amps on start up blow the dedicated breakers, unless you use magnetic shunt breakers. I was with the electrician during the wiring the whole time. I have two circuits dedicated to the amp case. The three two channel power amps powering the front right and left speakers would always blow the breaker unless it was a magnetic shunt breaker. I manually stagger start up. The amps start from 24 volt relays. The front right and left amps are on one relay, the amps for the center on another, the surrounds and Atmos ceiling speakers on another and the rear speaker amps on another, for a total of nine two channel amps for 18 audio channels total.

Newer amps have soft start circuits for this reason. Older amps, mine are close to 20 years old now do not have soft start circuits.
Plausible. But I'd need to know your exact situation to understand what's actually going on. Breakers are able to withstand surges. To a point, of course.

I have old amps too, late 90s. I stand by what I said and would look everywhere else first. If I was an electrician, I would be more than happy to take someone's money and install dedicated breakers.
 
TLS Guy

TLS Guy

Seriously, I have no life.
Plausible. But I'd need to know your exact situation to understand what's actually going on. Breakers are able to withstand surges. To a point, of course.

I have old amps too, late 90s. I stand by what I said and would look everywhere else first. If I was an electrician, I would be more than happy to take someone's money and install dedicated breakers.
OK, here is a picture of the bank of amps taken during construction.



The home has two panels, which are virtually back to back. One panel is in the studio chase, the other is on the same wall but faces the mechanical room.

I worked closely with the electrician, and made sure the AV room and the other systems were powered the way I wanted. I was present the whole time any wiring for the audio systems was done. In addition I planned and designed the whole house ground plane, and paid especially attention to the ground plain layout in the AV room chase. This was so that the system was dead quiet, and it is.

The electrician could not understand that magnetic shunt breakers would be required for the dedicated power amp circuits.

As soon as the front three power amps in that picture, which power the front right and left speakers, the breakers tripped immediately. So I installed the magnetic shunt breakers, and the breakers have not tripped since. The total audio power from that bank of amps is over 3000 audio watts. So no clipping here.

The amps are all started via 24 volt relays.



If you look at the three illuminated red switches in the first rack, from left to right, the left switch turns on the three amps for the left and right main speakers and also the fan that draws air up over the amp cases and exhausts it from the roof. The next switch is for the surrounds and the the ceiling atmos speaker amps, so three two channel amps, the next turns on the the two channel amp for the center speaker, the one on the right, the two, two channel amps, for the rear backs. Only the surrounds and ceiling speakers are passive, so there are 18 individual amp channels.

So, that is my situation, and both myself and my electrician know our business. So yes, amps can trip breakers.
 
Speedskater

Speedskater

Audioholic General
Plausible. But I'd need to know your exact situation to understand what's actually going on. Breakers are able to withstand surges. To a point, of course.
It's common for big power amplifiers to draw a lot of current charging up their big capacitors at turn-on.
Some amplifiers have a soft-start circuit to avoid this problem (but designing soft-starts is tricky).
The pros often use a power-on sequencer to avoid the problem if they have several amps on one circuit.
 
H

Hobbit

Audioholic Chief
OK, here is a picture of the bank of amps taken during construction.



The home has two panels, which are virtually back to back. One panel is in the studio chase, the other is on the same wall but faces the mechanical room.

I worked closely with the electrician, and made sure the AV room and the other systems were powered the way I wanted. I was present the whole time any wiring for the audio systems was done. In addition I planned and designed the whole house ground plane, and paid especially attention to the ground plain layout in the AV room chase. This was so that the system was dead quiet, and it is.

The electrician could not understand that magnetic shunt breakers would be required for the dedicated power amp circuits.

As soon as the front three power amps in that picture, which power the front right and left speakers, the breakers tripped immediately. So I installed the magnetic shunt breakers, and the breakers have not tripped since. The total audio power from that bank of amps is over 3000 audio watts. So no clipping here.

The amps are all started via 24 volt relays.



If you look at the three illuminated red switches in the first rack, from left to right, the left switch turns on the three amps for the left and right main speakers and also the fan that draws air up over the amp cases and exhausts it from the roof. The next switch is for the surrounds and the the ceiling atmos speaker amps, so three two channel amps, the next turns on the the two channel amp for the center speaker, the one on the right, the two, two channel amps, for the rear backs. Only the surrounds and ceiling speakers are passive, so there are 18 individual amp channels.

So, that is my situation, and both myself and my electrician know our business. So yes, amps can trip breakers.
Cool setup. Are you an EE too when we're not playing with your system?

I'm sticking to my guns on this one. Agree there's always exceptions. Your setup is probably one of them. But most of mortals aren't building commercial, or commercial like, systems for our home theaters.

My recommendation is to always start simple. My experience tells me that house wiring isn't always wired the way you may think by the breaker label. As the second post in this thread said, first look close at what else is on the circuit. This means checking what else in the house may be on that circuit. Not just what in the immediate room. I even gave a case and point in my own house.

Then I would want to know which amps he actually has. I think of crowns as relatively easy loads. A quick search of their website:

Many Crown amplifiers include "Soft Start," a feature designed to limit inrush current. Worst-case peaks for amplifiers without Soft Start may reach as high as 150 amperes; however, such numbers seldom have bearing on practical operation. For example, it is not unusual to find 3 or 4 Crown Micro-Tech amplifiers on a single 15A or 20A branch circuit without tripping breakers at turn-on. There are a couple of reasons why this is possible. First, peak inrush current is usually of such short duration that the breaker will not trip (maximum duration is approximately 18 msec). Second, Crown amplifiers are designed with design tolerances in the power supply start-up circuitry to make it highly unlikely for more than one amplifier channel to come out of standby during the same 18 msec interval.

If nuisance circuit breaker tripping is a concern, "motor-start" circuit breakers, which are designed to withstand the large inrush currents from electrical motors, may be used in place of standard circuit breakers. Contact a licensed electrician for more information about circuit breaker requirements and electrical codes in your area.


Ultimately, my last recommendation would be to put in a dedicated circuit for his system. I would recommend changing the existing breaker (I believe I said that could be the cause) before going this route. I do like Crown's recommendation for a motor start breaker if it does need to be changed. Didn't think of that.

I agree you need to know what you're doing. The espresso machine I'm eyeballing says you need a 20A breaker. Fortunately, knowing it was intended for small shops and after seeing the heater output, I knew to look at the power requirements.

Cheers!
 
TLS Guy

TLS Guy

Seriously, I have no life.
Cool setup. Are you an EE too when we're not playing with your system?

I'm sticking to my guns on this one. Agree there's always exceptions. Your setup is probably one of them. But most of mortals aren't building commercial, or commercial like, systems for our home theaters.

My recommendation is to always start simple. My experience tells me that house wiring isn't always wired the way you may think by the breaker label. As the second post in this thread said, first look close at what else is on the circuit. This means checking what else in the house may be on that circuit. Not just what in the immediate room. I even gave a case and point in my own house.

Then I would want to know which amps he actually has. I think of crowns as relatively easy loads. A quick search of their website:

Many Crown amplifiers include "Soft Start," a feature designed to limit inrush current. Worst-case peaks for amplifiers without Soft Start may reach as high as 150 amperes; however, such numbers seldom have bearing on practical operation. For example, it is not unusual to find 3 or 4 Crown Micro-Tech amplifiers on a single 15A or 20A branch circuit without tripping breakers at turn-on. There are a couple of reasons why this is possible. First, peak inrush current is usually of such short duration that the breaker will not trip (maximum duration is approximately 18 msec). Second, Crown amplifiers are designed with design tolerances in the power supply start-up circuitry to make it highly unlikely for more than one amplifier channel to come out of standby during the same 18 msec interval.

If nuisance circuit breaker tripping is a concern, "motor-start" circuit breakers, which are designed to withstand the large inrush currents from electrical motors, may be used in place of standard circuit breakers. Contact a licensed electrician for more information about circuit breaker requirements and electrical codes in your area.


Ultimately, my last recommendation would be to put in a dedicated circuit for his system. I would recommend changing the existing breaker (I believe I said that could be the cause) before going this route. I do like Crown's recommendation for a motor start breaker if it does need to be changed. Didn't think of that.

I agree you need to know what you're doing. The espresso machine I'm eyeballing says you need a 20A breaker. Fortunately, knowing it was intended for small shops and after seeing the heater output, I knew to look at the power requirements.

Cheers!
The correct term for a motor start breaker is a magnetic shunt breaker, and that is what you need to look for.

No I'm not an EE. I am a retired physician, but this has all been a huge passion of mine since I was seven years old.

If you have not already seen them, these are the other views showing the speakers.





Part of the museum end of the system.



So it is a domestic AV room. But you can edit and master a CD to Redbook specs in the room.
 
Last edited:
H

Hobbit

Audioholic Chief
The correct term for a motor start breaker is a magnetic shunt breaker, and that is what you need to look for.

No I'm not an EE. I am a retired physician, but this has all been a huge passion of mine since I was seven years old.

If you have not already seen them, these are the other views showing the speakers.





Part of the museum end of the system.



So it is a domestic AV room. But you can edit and master a CD to Redbook specs in the room.
That's a gorgeous setup! :cool:
 

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