Power amplifiers, with the exception of class A, may have a high instantaneous power draw; computers usually don't. A UPS that has been designed for general use should be rated for a peak load higher than the maximum power amplifier draw. The surge must be delivered to the power amplifier without clipping / current limitation to avoid a reduced power amplifier dynamic at full load. If the UPS is a "line interactive" type, the AVR and the mains EMI filter are still available even when the battery don't work. If it is the double conversion type, the DC/AC converter does have a separate filter and there is no guarantee that the output total harmonic distortion is lower than the mains. You need to measure it to be sure.
The main element is the transformer. If there is a large iron trafo, it is quasisenoidad. If small ones of ferrite but no large toroidal inductors, also. But if no transformer anf large toros, it is a sine syntetizer. They are the best although the more delicate a and large self power consumption.
Eh I know something about these devices. Just leave these out of audio as it will be a frustrating experience. Better connect your pc to it.
Protection of audio equipment against mains contaminants like high voltage transients, RF can be done with good netfilters with builtin MOVs etc. Except for the rare very well thought out expensive solutions the passive approach is very hard to beat. No batteries, no maintenance, no heat, no noise. Difficult concepts to some
Also better than no filtering in many cases.
Protection of audio equipment against mains contaminants like high voltage transients, RF can be done with good netfilters with builtin MOVs etc. Except for the rare very well thought out expensive solutions the passive approach is very hard to beat. No batteries, no maintenance, no heat, no noise. Difficult concepts to some
Also better than no filtering in many cases.
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Wrong! An online UPS is active all the time. The mains charges a battery and powers the DC rail via a rectifier. Both supply power to an inverter. The load is connected to that inverter. The load is therefor protected against black-outs, brownouts, transients etc. There is a lot going on with (regulated) IGBT rectifiers and IGBT inverters to maintain high power efficiency, stable output voltage and high reliability.
This with online double conversion types so AC to DC and then DC to AC. The UPS is always inbetween mains and load.
Eh I use mains filters from scrapped young single phase UPSes in DIY power distributors like my Fritz as described here somewhere. Ready made ones by Monster like the 5100 and 7000 are good but hard to find. Belkin also made very good ones in the past. My opinion to myself is that if I can not build mains filters/distributors, linear PSUs myself I should quit this hobby so I only use DIY and semi DIY stuff.
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In fact in an online ups the battery is charged by an independent battery charger. The mains is rectified and then re-converted into a PWM modulated sine wave. Filtering it revonverts a very good sine wave, by far larger better than those of the grid. I repaired several of them, various brands, same schema.
Flip the UPS upside down. Also, note how many things you can get these days that run off of a DC brick. I have kept mine "automotive DC range" for 5 years now. It's charged from a 50W panel.
As to what happens in winter, well, eventually the DC line cuts me off. However, before that occurs a smart plug (not pic'ed) will turn on a mains charger and close a dry contact to charge the battery directly from the mains. Not all the way, just a bit. (For a week this year it got so bad I left the backup charger running at 12.0V and found it added very little noise.)
As to what I get out of it, about 10-15KwH per year. So a couple of quid a year. I also get a silent, floating, ~12VDC line.
On using an off grid battery + invertor setup to create an isolated, floating AC mains circuit... Even if that AC mains feed comes from a UPS. I STRONGLY encourage you to do your research carefully. Very carefully. Interconnecting a device running from grid mains to a device running from unsync'd off grid mains, even just an audio cord, is highly likely to cause a some magic smoke be released in the best case and a house/line wide fault causing damage to lots of equipment in the worst.
UPS's have circuitry and protocols to avoid this. Once you start using things out of their intended use or with equipment not expecting to be powered from a UPS bad stuff can happen.
If you can, stick to DC.
As to what happens in winter, well, eventually the DC line cuts me off. However, before that occurs a smart plug (not pic'ed) will turn on a mains charger and close a dry contact to charge the battery directly from the mains. Not all the way, just a bit. (For a week this year it got so bad I left the backup charger running at 12.0V and found it added very little noise.)
As to what I get out of it, about 10-15KwH per year. So a couple of quid a year. I also get a silent, floating, ~12VDC line.
On using an off grid battery + invertor setup to create an isolated, floating AC mains circuit... Even if that AC mains feed comes from a UPS. I STRONGLY encourage you to do your research carefully. Very carefully. Interconnecting a device running from grid mains to a device running from unsync'd off grid mains, even just an audio cord, is highly likely to cause a some magic smoke be released in the best case and a house/line wide fault causing damage to lots of equipment in the worst.
UPS's have circuitry and protocols to avoid this. Once you start using things out of their intended use or with equipment not expecting to be powered from a UPS bad stuff can happen.
If you can, stick to DC.
Note. I don't think there are any magical solutions between floating or earth referenced. Both have their evils. My DC system is floating, but some of my sources are not. In fact some of them have SWPS leakage current on their grounds. So, everything starts floating and flowing current around the place. However, if I earth the system, I simply common mode float the battery - (or + depending how I'm feeling) and take on all that noise.
I also hope for no lightening strikes or streamers nearby. I'm not sure I want to measure what that system floats at during a thunderstorm.
I also hope for no lightening strikes or streamers nearby. I'm not sure I want to measure what that system floats at during a thunderstorm.
Not familiair with this model, but a warning: most cheap UPS systems for computer backup use one or more standard 12V gel lead batteries.
A 800VA probably has 1 or 2 batteries if it is a budget one, 12 or 24 V in total. Do the math.
At least 66 resp 33 amps current draw from the battery pack on full load, way above what is healthy for such gel batteries. My experience is that you are lucky to get 2 or 3 cycles out of such system before the batteries die.
There are of course better models, check the battery voltage on yours. If it is 48V or higher, things start to look a bit better.
A 800VA probably has 1 or 2 batteries if it is a budget one, 12 or 24 V in total. Do the math.
At least 66 resp 33 amps current draw from the battery pack on full load, way above what is healthy for such gel batteries. My experience is that you are lucky to get 2 or 3 cycles out of such system before the batteries die.
There are of course better models, check the battery voltage on yours. If it is 48V or higher, things start to look a bit better.
There will be too much noise if running Class D amps.
Not worth it, I think.
You can turn the concept around, and use it as a fancy charger, use the batteries to drive the amp directly.
48V is quite enough for a home setup.
That will be very clean power, use thick wires.
And one 12V battery can be tapped for the pre-amp section.
Not worth it, I think.
You can turn the concept around, and use it as a fancy charger, use the batteries to drive the amp directly.
48V is quite enough for a home setup.
That will be very clean power, use thick wires.
And one 12V battery can be tapped for the pre-amp section.
It is a nice UPS from a reputable brand, you can use it for audio if you don't mind the fan noise and if the battery is good enough to keep the double conversion active. The protection logic will force a bypass on mains when battery voltage is out of spec (shorted or open circuit). It will keep the output stable within 1% and very low harmonic distortion buy the amount of residual EMI is unknown. If you have a line filter, you can keep it as good measure.
Using a regular computer UPS as battery charger needs further checks. This is a "high-end" unit with many safety features, it may just shut down with a error code if the control logic of the carger detects a unwanted load on the battery. On low-end "dumb" UPS, the galvanic separation between battery and mains is not guaranteed. The setup described by Naresh would work fine with something like the Volt Polska Sinus Pro 500E. Tme.eu is the main distributor for Europe, I believe. It is a combination of battery charger, DC/AC inverter (without battery) and a mains/DC automatic switch. You may use any 12V LiFePo4 or Pb external battery and connect the load to the 12V battery (trough a fuse) and/or to the 230V inverter output.
Using a regular computer UPS as battery charger needs further checks. This is a "high-end" unit with many safety features, it may just shut down with a error code if the control logic of the carger detects a unwanted load on the battery. On low-end "dumb" UPS, the galvanic separation between battery and mains is not guaranteed. The setup described by Naresh would work fine with something like the Volt Polska Sinus Pro 500E. Tme.eu is the main distributor for Europe, I believe. It is a combination of battery charger, DC/AC inverter (without battery) and a mains/DC automatic switch. You may use any 12V LiFePo4 or Pb external battery and connect the load to the 12V battery (trough a fuse) and/or to the 230V inverter output.