I get a split second voltage sag (aka brown-out) when my roof mounted air conditioner unit kicks in, which cuts the audio from my vintage Pioneer M-22 amp for a second. We've had the sag since we bought a new unit four year ago, and it's never switched anything off or cut out sound, but now I have this amp which is susceptible to power fluctuations.
Our air conditioner tech took a look, he said the compressor is drawing a lot of power when it first kicks in (which apparently isn't unusual) then stabilizes, so he's not surprised by the momentary sag. He recommended getting an electrician to look at the breaker panel and wiring (which are not old). Speaking to a few electricians on the phone, they all have different theories, and I'm reluctant to get into the expense of a wild goose chase if this ultimately can't be fixed?
It's worth mentioning that it's a Japanese amp, so I'm using a step-down converter to feed it 100v. I could dump the converter if I had a variable device I could just set to 100v.
I know the ideal solution would be something like a PS Audio Power station (AC regenerator), but I don't want to spend a few grand. I'd rather spend a couple of hundred, tops.
There are uninterruptible power supplies, which are often used in the computer arena (kicks in a battery if the voltage is lowered) but I don't know how well that would get along with a 30w amplifier?
There are also variacs, constant voltage transformers and servo transformers, but I've no idea if they're ideal for this application? I hear CVTs are noisy.
Our air conditioner tech took a look, he said the compressor is drawing a lot of power when it first kicks in (which apparently isn't unusual) then stabilizes, so he's not surprised by the momentary sag. He recommended getting an electrician to look at the breaker panel and wiring (which are not old). Speaking to a few electricians on the phone, they all have different theories, and I'm reluctant to get into the expense of a wild goose chase if this ultimately can't be fixed?
It's worth mentioning that it's a Japanese amp, so I'm using a step-down converter to feed it 100v. I could dump the converter if I had a variable device I could just set to 100v.
I know the ideal solution would be something like a PS Audio Power station (AC regenerator), but I don't want to spend a few grand. I'd rather spend a couple of hundred, tops.
There are uninterruptible power supplies, which are often used in the computer arena (kicks in a battery if the voltage is lowered) but I don't know how well that would get along with a 30w amplifier?
There are also variacs, constant voltage transformers and servo transformers, but I've no idea if they're ideal for this application? I hear CVTs are noisy.
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Scroll down to "Air Conditioners " and read the detail in this Electrical Engineering technical/scientific testing pdf --in great detail ,of current drawn under US/UK mains voltages --well worth reading.
This isn't a "fault" per se but the inability of your mains supply to sustain a very high current load ( under normal household supplies ) .
By using a step-down transformer to feed 100 Volts I take it you live in the EU/UK or a country with 230 volts AC rms ( nominal ) ?
In the USA and some European countries heavy current drawing domestic equipment is helped by 2 or 3 phase supplies but obviously not in your case .
Really if you want this fixed permanently forget all the gadgets contact your electric utility company for advice and help and they will advise .
Most of them anyway will only output a ratio of what is inputted .
Yes you can buy crystal/digital controlled /battery operated AC very low distortion digital voltage generators but you need a BIG battery and have to keep them charged .
I would be on the phone to my utility company long ago as my first stop.
https://pdfs.semanticscholar.org/efab/5f86224312a46816c04e7741fe9221cb341d.pdf
This isn't a "fault" per se but the inability of your mains supply to sustain a very high current load ( under normal household supplies ) .
By using a step-down transformer to feed 100 Volts I take it you live in the EU/UK or a country with 230 volts AC rms ( nominal ) ?
In the USA and some European countries heavy current drawing domestic equipment is helped by 2 or 3 phase supplies but obviously not in your case .
Really if you want this fixed permanently forget all the gadgets contact your electric utility company for advice and help and they will advise .
Most of them anyway will only output a ratio of what is inputted .
Yes you can buy crystal/digital controlled /battery operated AC very low distortion digital voltage generators but you need a BIG battery and have to keep them charged .
I would be on the phone to my utility company long ago as my first stop.
https://pdfs.semanticscholar.org/efab/5f86224312a46816c04e7741fe9221cb341d.pdf
Supply voltage 100V, 50Hz/60Hz
Power consumption 240W (Electrical Appliance and Material Control Law)
Circuit system Two steps of differentials, PP drive, two-step Darlington, parallel PP,
Pure complimentary OCL (a Class-A operation, DC amplifier stream composition)
The circuit has a number of protection against overheating from a constant at the output in the event of an output of the VC and overload. Each channel has its own relay and a pair of fuses directly on the ULF boards in each channel!
1. Correct the network wiring
2. Use high quality autotransformer 230v / 100v / 400w
3. Stabilizers have a reaction time
4. UPS have voltage with interference
5. Loss of capacity of the power supply capacitors is possible. Verify. Fix it.
6. Check the protection settings of the amplifier.
7. In a hopeless situation, switch the amplifier power supply to SMPS.
Power consumption 240W (Electrical Appliance and Material Control Law)
Circuit system Two steps of differentials, PP drive, two-step Darlington, parallel PP,
Pure complimentary OCL (a Class-A operation, DC amplifier stream composition)
The circuit has a number of protection against overheating from a constant at the output in the event of an output of the VC and overload. Each channel has its own relay and a pair of fuses directly on the ULF boards in each channel!
1. Correct the network wiring
2. Use high quality autotransformer 230v / 100v / 400w
3. Stabilizers have a reaction time
4. UPS have voltage with interference
5. Loss of capacity of the power supply capacitors is possible. Verify. Fix it.
6. Check the protection settings of the amplifier.
7. In a hopeless situation, switch the amplifier power supply to SMPS.
Why would a motor/generator smell bad? I know diesel backup generators are awful, but that’s not what’s powering it....
Try one of the power conditioners intended for pro audio (studio and/or portable PA - something like a Furman comes to mind). They are intended to deal with iffy power and don’t have the audiophile tax. The only possible issue would be if the response time isn’t fast enough, but my guess is it would be. Buy and try, if you can. You won’t need the most expensive one on the planet. They use multi-tap or CV transformers in them, Depending on model. CV transformers aren’t “noisy”, but do have about 10% distortion. Multi-tap transformers would have switching time, but they can make that one or two cycles of line frequency.
The other option would be a pure sine UPS. A 500 watt unit would do. Regular computer “backup supplies” are noisy, and the response time is t exactly spectacular since the cheap ones use mechanical relays. Still pretty fast, but would have a definite “Ka-chunk”, not to mention the square wave output.
Try one of the power conditioners intended for pro audio (studio and/or portable PA - something like a Furman comes to mind). They are intended to deal with iffy power and don’t have the audiophile tax. The only possible issue would be if the response time isn’t fast enough, but my guess is it would be. Buy and try, if you can. You won’t need the most expensive one on the planet. They use multi-tap or CV transformers in them, Depending on model. CV transformers aren’t “noisy”, but do have about 10% distortion. Multi-tap transformers would have switching time, but they can make that one or two cycles of line frequency.
The other option would be a pure sine UPS. A 500 watt unit would do. Regular computer “backup supplies” are noisy, and the response time is t exactly spectacular since the cheap ones use mechanical relays. Still pretty fast, but would have a definite “Ka-chunk”, not to mention the square wave output.
Why not just see if the amp can be tweaked and any time constant related to a mains drop out detector increased a little. It may be as simple as increasing the value of a cap.
Short of a moto-generator or a AC->DC->AC converter, you will not be able to stabilize the AC in voltage of the supply to the amp. The response time will not be fast enough. I monitor the current to my AC compressor and the spike is 50A for about 50mSec and quickly settles to 7A. Basically the motor is a dead short until it starts to spin. The mains voltage is going to droop a bit. I even notice a slight light flicker when the fridge kicks in. Compressors are tough loads. I know my house has an outdoor fusebox that splits out the AC(and other high current loads like the oven) right at the meter to minimize wiring resistance. The rest of the house has a separate fusebox inside for all the other stuff.
With all that said, something is different with the new AC if it worked before. Is the new AC bigger? Is it a different type (new inverter compressor)? Does it have a start kit and the previous did not?
And finally, I'd try throwing on a good RFI power filter if you have one just to see if maybe the spike is generating some noise on the line that is tripping the protection. Cheap check. And if you have a scope or know someone with one probe the line to see just how bad the line is when the AC kicks on. You'll need a storage scope since it is a one off event.
With all that said, something is different with the new AC if it worked before. Is the new AC bigger? Is it a different type (new inverter compressor)? Does it have a start kit and the previous did not?
And finally, I'd try throwing on a good RFI power filter if you have one just to see if maybe the spike is generating some noise on the line that is tripping the protection. Cheap check. And if you have a scope or know someone with one probe the line to see just how bad the line is when the AC kicks on. You'll need a storage scope since it is a one off event.
Look up power factor correction and see what is done on large scale power networks.
I have no idea the restrictions or requirements for domestic applications.
Every time I have looked into that for industrial purposes, the default was to go with more dedicated circuit capacity, even if the culprit was just one device.
I have no idea the restrictions or requirements for domestic applications.
Every time I have looked into that for industrial purposes, the default was to go with more dedicated circuit capacity, even if the culprit was just one device.
The reason I said--contact your utility company is that in the UK there are many companies who will UPRATE the presently available current supply to your home to over 70 KVA-----but-----for a price .
I am looking at two in England at this very moment.
UK Power Networks is one .
What do you need to upgrade | UK Power Networks
I am looking at two in England at this very moment.
UK Power Networks is one .
What do you need to upgrade | UK Power Networks
My experience is that older compressors are far worse about this than newer more efficient ones are. The old 3.5 ton unit when I moved into this place was terrible for dimming the lights. Both newer 4 ton ones we’ve had since you don’t even notice when they kick on. Being 2-stage units probably helps here. Brushless DC are probably even better - but I’m not spending that much to get a 30 SEER unit. 17 is enough, and the unit doesn’t dim the lights at start up.
I’ve had old washing machines that were as bad or worse than the old AC compressor. And they threw spikes on the neutral bus too, which was quite audible on the speakers.
The more efficient units will likely have lower hp compressors. I know when I updated my unit they had to put in a lower value circuit breaker as the new unit drew less power. And yes, anything pulling 120V like your washer is going to spike one phase of the 240 and the neutral, whereas the AC is 240 so the neutral is not affected. In fact, usually the neutral is not even connected on an outdoor AC unit.
OP here, thank you for the replies so far - it's really helpful. I'm British, but living in the US. So am stepping down from 120v the Japanese standard of 100v.
The Lennox AC Unit is only fours year old, and designed for a 2000 sq ft house. It was swapped out because the old unit was cranky, and this is more efficient.
Last night I was looking at voltage transformers, but as some people have suggested, I'll maybe try to fix the issue at the source - AC unit/circuit breaker panel/wiring.
The Lennox AC Unit is only fours year old, and designed for a 2000 sq ft house. It was swapped out because the old unit was cranky, and this is more efficient.
Last night I was looking at voltage transformers, but as some people have suggested, I'll maybe try to fix the issue at the source - AC unit/circuit breaker panel/wiring.
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Your important brownout comes because both AC and rest of equipment share a relatively inadequate/high resistance power wire.
I had a similar problem, with a speaker magnetizer pulling 46A at 220VAC ; although magnetizing pulse takes a couple seconds, it triggered my answering machine, erased microwave and TV settings, let alone blinked lights off, so I installed a separate 2 x 8mm wire just for it, straight from the utility pole.
That would be a 2 x 16mm wire @120V AC lines.
End of problems.
It will help you not only with that amplifier, but with everything else.
EDIT: correct the basic problem, don´t waste time and money with "patches".
I had a similar problem, with a speaker magnetizer pulling 46A at 220VAC ; although magnetizing pulse takes a couple seconds, it triggered my answering machine, erased microwave and TV settings, let alone blinked lights off, so I installed a separate 2 x 8mm wire just for it, straight from the utility pole.
That would be a 2 x 16mm wire @120V AC lines.
End of problems.
It will help you not only with that amplifier, but with everything else.
EDIT: correct the basic problem, don´t waste time and money with "patches".
The correct solution is to check and repair/upgrade the connection between the breaker panel and the AC unit. The quick and easy fix is to put a inexpensive inrush current limiter in series with the AC unit. There are several manufacturers, such as this one Limiting AC Motor Inrush Current of Air Conditioner
The problem isn’t between the breaker box and the AC, it is between the breaker box and the pole pig. Or the pole pig itself. Unless there is a corroded connection that can be fixed, you may be SOL as to fixing root cause and have to band aid it. Power company isn’t going to give out free upgrades - their responsibility is only to fix what is “broken”.
Well, you can´t assume that.
In principle I trust the utility company; .....
Home wiring? .... not that much.
If it were a local transformer problem ("pole pig") then brownouts should also happen at neighbouring homes fed from same line ... not too sure that´s happening.
In principle I trust the utility company; .....
Home wiring? .... not that much.
If it were a local transformer problem ("pole pig") then brownouts should also happen at neighbouring homes fed from same line ... not too sure that´s happening.
Not effecting neighbouring homes, just us with our demanding AC unit / lack of electrical bandwidth to deal with it. There have been so many good theories and ideas in this thread, that I'll find a reputable electrician and float them by him. I'm super grateful to you all.