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Uninterupted Power Supplies (UPS)

Discussion in 'Computing' started by BobRogers, Jul 2, 2012.

  1. BobRogers

    BobRogers Well-Known Member

    So we've had bad storms for the last two nights. Fortunately, our neighborhood still has power, but I'm thinking that a couple of UPS would be a good investment: one for the studio and one for the office to keep computers going for a little while and the cell phones charged.

    I haven't had any surge problems. The studio and the living room electronics are on Furman AR-1215 conditioners. Not top of the line, but not all that bad. At any rate, I'm interested in finding out my options, but I'm thinking about something that would give me a few minutes to shut down the studio, not something that would keep me up and running for hours. I don't have enough isolation to track during a thunderstorm. So I'm just looking to keep from loosing a few minutes of work during a mixing session.

    What do you guys use? What do you recommend? I know we talked about this a while ago, but there seem to be a lot of new inexpensive consumer models out there.
     
  2. TheJackAttack

    TheJackAttack Distinguished Member

    There are definite differences in the protection circuitry of UPS units. I use quite a few consumer level units at the campground in the summer and the rule of thumb is once it has been smoked it goes in the trash regardless of apparent condition. Basically the protection on these units are bits that are designed to destroy themselves when overloaded. A decent mid level unit might take one jolt of 220 for instance but the next jolt will send the power straight through to the equipment. Basic professional level units will have "clamping" circuitry like the Furman conditioner that doesn't self destruct upon overload. They also cost 8 times more. I have several Furman units that I refurbished to working condition or I wouldn't be able to afford them in my audio business.

    That said, used in conjunction with your Furman line conditioner, a not-bottom-line UPS in the 1000ah range ought to provide protection and about 15 minutes of time on a computer and decent sized screen. The main benefit I have seen is protection from brown outs more than surges. I am well aware that technically modern power supplies will handle a "range" of current but my experience is that computerized gear hates low current a lot like an amp rack puts out crappy sound/minimal headroom in low current situations at a live show.
     
  3. Boswell

    Boswell Moderator Distinguished Member

    A few pointers to a suitable UPS for audio studio work:

    (1) Check the UPS max continuous output current (as opposed to the Ah capacity) and specify a unit that has at least 50% more than the sum current taken by the gear you aim to power. If you can't find the mains input current figure for each piece of gear, use a meter measure it at the low end of the input voltage range (e.g. 105V in the US).

    (2) Make sure the UPS is a continuous-synthesis type, not the switchover-on-mains-failure type.

    (3) Avoid squarewave or modified-squareware output units. True sinewave outputs are expensive and heavy, but there are UPS units that will produce pseudo-sinewave outputs.

    (4) It's useful if the UPS output frequency locks to mains input frequency during normal operation.

    (5) Use the surge power conditioner in front of the UPS.
     
  4. TheJackAttack

    TheJackAttack Distinguished Member

    As always, Boswell has made very good points. Continuous sine wave at least in the US units is usually accomplished through full time conversion from AC to battery and then back to output AC.
     
  5. RemyRAD

    RemyRAD Well-Known Member

    Like the other smart people here, I too was going to recommend something like a Liebert computer power system. In these devices, you're always running off of batteries which are then output to true sine wave generated output amplifiers. So loss of power and even intermittent hits, don't affect continuous output power. But a Liebert is likely to set you back more than $4000. Maybe over at Virginia Tech you might be able to obtain some used units if they have upgraded to newer devices? But that might also require a change of batteries to plenty of new batteries? I know that's what one of my friends and colleague over at Sheffield Recordings Ltd. told me I needed to have 21 years ago. It was an expense I could not justify. But then John was a millionaire/is a millionaire whose Italian father had a construction company where I believe Jimmy Hoffa is buried under his studio. LMAO but there could be some truth to that possibility? We'll never know.

    Has anyone ever seen Jimmy Hoffa lately? It's one of the great mysteries of the world. And no college professor can tell you where he is today. But it's certainly a mathematical probability that something like that actually happened. So start doing your math Bob and let us know what you come up with? There might be an award in finding his whereabouts which will provide you with the budget for a Liebert?

    I only have a power isolation transformer and cheap switchover UPS's, as recommended to me by K00STER McAllister.
    Mx. Remy Ann David
     
  6. MadMax

    MadMax Well-Known Member

    I use the APC line to backup my servers and workstations.

    All I'm looking to do is get 7 minutes to safely shut down the spindles. After that, I'm not worried about anything other than not being up and running during storms.

    My biggest asset during the storm/hurricane season is Weather Forecast & Reports - Long Range & Local | Wunderground | Weather Underground - if bad weather is forecast, I keep a screen up in real-time to assess when it's time to shut it down and keep both my clients and my gear as safe as possible.
     
  7. TheJackAttack

    TheJackAttack Distinguished Member

    Max, I'd think with your history you would know EXACTLY when lighting is around!
     
  8. Boswell

    Boswell Moderator Distinguished Member

    ...despite being in the Dark Pines Studio!
     
  9. MadMax

    MadMax Well-Known Member

    Yer' darn Skippy!!

    Actually, it's all but impossible to hear storms approaching until the storms are right up on me. If I'm listening at anything over medium volume, I can't hear the LF rumble of thunder at all.

    Which is why I keep a pretty close eye on the weather radar. When I see storms within 15 minutes, I shut it ALL down.

    I'm not toooo worried about hurricanes, tornado's I definitely take serious... but a good ol' thunderstorm... I take VERY serious, (but I hope I'm allowed that much leeway.)
     
  10. TheJackAttack

    TheJackAttack Distinguished Member

    Max, I think we can cut you a little slack! ;-)

    We just had one of the main 42circuit panels blow Saturday morning at 09:15. And the forty year old 225v GE main breaker. Out here in nowheresville TRY finding an electrical supply open on the weekend. We ended up having to replace the entire panel by ripping out the guts of the burnt panel and mounting a new panel exactly on top and pulling through the wires. We even had to main tap off another breaker temporarily. Now after we get the new main breaker in and switch the main tap all that's left is the state inspector. Even Dave might approve the work.

    To come back to topic however, I was able to keep the network and office running for six hours before I had to grab the gennies. I didn't lose a single piece of computer or networking equipment. Of course I swap batteries every 3-4 years and label the dates and any UPS that has been jolted is replaced regardless of apparent functionality.
     
  11. MadMax

    MadMax Well-Known Member

    Just curious... Do/did you have a gennie cutover switchgear in place?

    ...and just to take the topic a tad further in the thought process (and hopefully the smoke detectors won't go off in the meantime from me thunkin' so hard.)

    The act of purchase/installation of a gennie would (IMHO) necessitate using a constant conversion UPS to handle the failover time as well as filtration from the gennie.
     
  12. TheJackAttack

    TheJackAttack Distinguished Member

    No. The gennies I have at the campground are just portables that we use to power up critical areas like the registration desk. We are in the process of finding a three phase gennie for the sewage lift station because if that fails we are in deep $*^t. Literally. It is possible to feed the three phase converter at the station from it's feeder panel but I'd rather have a gennie big enough to run the motors at the pit.

    That brings up another story. Right before I got out of the Corps, I was moonlighting a sound reinforcement gig at Camp Pendelton for a defacto military nam show. Congressman and product representatives were there such as Barret, Triton and Hummer etc. The power was provided by the Corps via Motor T. Well one of those privates juiced the line with 240 VAC even though they had been running just fine all morning properly on 120VAC. We were the only ones there with UPS protection. After that we were the only ones there with functioning sound gear. The UPS units were even reconditioned at APC for the permission to use the story. I don't know if they ever did though.
     

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