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Church and H.O.W. – Forums for HOW Sound and AV - Your Displayed Name Must Be Your Real Full Name To Post In The Church and HOW Forums => Church Sound => Topic started by: Lance Rectanus on August 20, 2016, 05:09:54 PM
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I am working on a proposal for our first digital board: something akin to a Behringer X32 or a Soundcraft Si Impact. I am looking at UPS's and want to do this right and I've read here that what I want is a "true sine wave" UPS. As I understand it, this means that you're always running off the battery with corrected voltage available even during brown-outs, surges and spikes. After a quick Amazon search I came up with the APC SMC-1000 as a typical, entry-level version. Is this what I'm looking for? In addition to the mixing console (@ 130 W at 120v) I would like to protect a desktop computer w/LCD monitor and my 2-channel wireless receiver: 500 watts max. I'm not looking to run the system if we lose power, more to protect it against surges and sags and to give me time to shut it down controllably if power is lost completely.
Am I on the right path with something along these lines? Any minefields that I should avoid? I'm looking at purchasing in the next 6-12 months, so whatever I spec this month will probably change by the time I purchase.
Linky: https://www.amazon.com/APC-SMC1000-Smart-UPS-120-Volt-Uninterrupted/dp/B007ZT2K9I/ref=sr_1_18?s=pc&ie=UTF8&qid=1471724998&sr=1-18&keywords=ups+battery+backup&refinements=p_89%3AAPC (https://www.amazon.com/APC-SMC1000-Smart-UPS-120-Volt-Uninterrupted/dp/B007ZT2K9I/ref=sr_1_18?s=pc&ie=UTF8&qid=1471724998&sr=1-18&keywords=ups+battery+backup&refinements=p_89%3AAPC)
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Why would you think that you need a "true sine wave" UPS? Most modern components have SMPS (power supplies) and don't much care what kind of AC power they receive. The only reason to have a UPS is when you have a power brown-out or total outage. Don't buy into another audiophile myth.
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But on the other hand, a "true sine wave" UPS will probably generate less interference than the budget ones do.
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Why would you think that you need a "true sine wave" UPS? Most modern components have SMPS (power supplies) and don't much care what kind of AC power they receive. The only reason to have a UPS is when you have a power brown-out or total outage. Don't buy into another audiophile myth.
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But on the other hand, a "true sine wave" UPS will probably generate less interference than the budget ones do.
As I said in my post, I am going off of what I have read, repeatedly, on these forums that the true sine wave ups is the way to go. They are significantly more expensive than the equivalent "home" types. That's why I'm posting here for others' input.
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Why would you think that you need a "true sine wave" UPS? Most modern components have SMPS (power supplies) and don't much care what kind of AC power they receive. The only reason to have a UPS is when you have a power brown-out or total outage. Don't buy into another audiophile myth.
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But on the other hand, a "true sine wave" UPS will probably generate less interference than the budget ones do.
That stepped sine wave will introduce interference in the audio path one way or another.
Unless the ups is an online ups (always switched in) the battery may drain quickly due to dirty power and the ups will run down very quickly.
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That stepped sine wave will introduce interference in the audio path one way or another.
Unless the ups is an online ups (always switched in) the battery may drain quickly due to dirty power and the ups will run down very quickly.
In many years of always running my digital consoles on UPS power I have never experienced noise induced by the UPS. I have never, to my knowledge, used an online UPS. With distributed I/O made possible with Dante I use several small residential type "brick" UPSs at each digital device, all with no extra noise. I have been in situations where the power failed and we relied on the UPS and the changeover was seamless even though the UPS was not the "online" type.
If you are often running on undersized, under regulated, generators it may happen that the UPS will kick over to battery even though you still have generator power, running down your battery without you knowing you were even running on UPS, this may be a situation where an online UPS would be better.
Mac
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In many years of always running my digital consoles on UPS power I have never experienced noise induced by the UPS. I have never, to my knowledge, used an online UPS. With distributed I/O made possible with Dante I use several small residential type "brick" UPSs at each digital device, all with no extra noise. I have been in situations where the power failed and we relied on the UPS and the changeover was seamless even though the UPS was not the "online" type.
If you are often running on undersized, under regulated, generators it may happen that the UPS will kick over to battery even though you still have generator power, running down your battery without you knowing you were even running on UPS, this may be a situation where an online UPS would be better.
Mac
I have had stepped sine wave ups induce bad noise into audio. Once it happened on a festival with a very big PA when I was the video guy and wanted to protect the video tape recorder from making tape sallad should the power go out.
I had to move the power cord and the ups kicked in. It scared the shit out of everyone when the FoH blasted the ups noise.
I thought that they were going to throw me out in tar an feather...!
I'm only using pure sine wave since that incident.
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I have had stepped sine wave ups induce bad noise into audio. Once it happened on a festival with a very big PA when I was the video guy and wanted to protect the video tape recorder from making tape sallad should the power go out.
I had to move the power cord and the ups kicked in. It scared the shit out of everyone when the FoH blasted the ups noise.
I thought that they were going to throw me out in tar an feather...!
I'm only using pure sine wave since that incident.
How did you determine it wasn't caused by the change in the grounding scheme when you unplugged the main power? That is a very common cause of noise when video and audio are interfaced. If the UPS was the cause it should have caused that noise when a single tape machine was hooked up to a local speaker and run on the UPS. Did you test that?
Mac
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How did you determine it wasn't caused by the change in the grounding scheme when you unplugged the main power? That is a very common cause of noise when video and audio are interfaced. If the UPS was the cause it should have caused that noise when a single tape machine was hooked up to a local speaker and run on the UPS. Did you test that?
Mac
No, I didn't test that. It happened during the first act and I was just the video guy. I had a isolated multifeed from the FoH console that went into my yamaha 02r so in theory this shouldn't have happened. There was probably some other ground path that we didn't think of at the time.
I have tried to use a stepped sinewave ups as a poor mans battery for recording sound for outside locations and this did not work either due to induced noise from the ups.
Perhaps you are right that it is a grounding issue, but since I've had no issues with pure sinwave ups's I'll stay that route as my own personal experience with the stepped ups'es has been bad.
One practical benefit of using a online ups is that it is galvanic isolated device between the power input and output.
Another time when I was doing sound for a tv-show on a temporary location and the dmx-mixer crashed every now and then. A cheap offline ups was inserted but it didn't help. Next day I brought one of my online ups and the dmx-mixer never crashed a single time after that. I don't know anything about dmx-mixers but I was told it was an expensive recognised brand.
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No, I didn't test that. It happened during the first act and I was just the video guy. I had a isolated multifeed from the FoH console that went into my yamaha 02r so in theory this shouldn't have happened. There was probably some other ground path that we didn't think of at the time.
I have tried to use a stepped sinewave ups as a poor mans battery for recording sound for outside locations and this did not work either due to induced noise from the ups.
Perhaps you are right that it is a grounding issue, but since I've had no issues with pure sinwave ups's I'll stay that route as my own personal experience with the stepped ups'es has been bad.
One practical benefit of using a online ups is that it is galvanic isolated device between the power input and output.
Another time when I was doing sound for a tv-show on a temporary location and the dmx-mixer crashed every now and then. A cheap offline ups was inserted but it didn't help. Next day I brought one of my online ups and the dmx-mixer never crashed a single time after that. I don't know anything about dmx-mixers but I was told it was an expensive recognised brand.
At 7 pounds (li ion battery) and the form factor of the handle being on top I keep saying I am going to buy a couple of these:
https://www.amazon.com/dp/B01AFLNSI4?psc=1
They are inverter's with a built in charger so they float off the battery/rectifier. This would run an x32 and rack for an hour. More than you could ever need.
https://www.amazon.com/dp/B01AFLNSI4?psc=1
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At 7 pounds (li ion battery) and the form factor of the handle being on top I keep saying I am going to buy a couple of these:
That was a quick 1/2 of research.
As I thought eBay is festooned with surplus 48v telecom rectifier modules. These modules cost the carriers 1000's of dollars and are super stable switch mode chargers. At about 7lbs you can get a 24amp unit. That's about 1000 watts of 110v give or take the efficiency factor of the inverter.
While the above referenced unit on amazon is cute for the 1/2 the price you can get a high quality 700w inverter, about 30 amp hours of li-ion batteries and an inverter. A little bit of wiring, set your float and equalize voltages and you have a light weight full time power module with a decent amount of time to run an LED flood lamp for load out once the genny is shut down.
Update:
Hopefully someone will check my math.
The base cell voltage for a Li-ion is 3.7v, 13 of them gives you a 48V cell @ 4000mah or 4 ah
5 cel banks would give you 20 ah @ 48v or about 750 watts @ 110v assuming a bit of inversion loss.
So $50.00 or less in batteries, - $60.00 for the inverter and $30.00 for the charging module. Add another $15.00 for a charging controller with a nice display on it.
That's $150.00 for q hour of 700 watt pure sine wave inverter power. Fairly cool.
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... what I want is a "true sine wave" UPS. As I understand it, this means that you're always running off the battery with corrected voltage available even during brown-outs, surges and spikes.
Apples and oranges mixed alert.
A "true sine wave UPS" outputs, well, a true sine wave, as opposed to a stepped sine wave, or square waves.
A UPS that "always running off the battery with corrected voltage available even during brown-outs, surges and spikes" is an "online" UPS, "always online", or a "dual conversion", or something similar. UPSs that are not "online" normally provide power directly from the mains, only switching to the inverter if the mains fails.
You can have any combination of online and standby, and true sine versus stepped.
As others have noted, if you're protecting digital electronics, it'll have a switched mode power supply, and wont care what the input waveform looks like, even DC is acceptable to most SMPSs. If one is using stepped output UPS and there is noise appearing in the audio, then there is another problem present.
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The company I worked for moved away from the "always online" UPSs because when the battery went bad, after three years like they always do... It would, without much warning, kill the output of the entire unit. These were in online 24/7 installations. Maybe this has been remedied with the current crop, but it only took getting bit once.
Sent from my iPhone using Tapatalk
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If one is using stepped output UPS and there is noise appearing in the audio, then there is another problem present.
+1
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The company I worked for moved away from the "always online" UPSs because when the battery went bad, after three years like they always do... It would, without much warning, kill the output of the entire unit.
This is the Lord's way of reminding you that you aren't doing preventative maintenance....