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Gear / Technical Help => Remote Power => Topic started by: Patrick on September 10, 2011, 01:32:47 PM

Title: Small UPS (power supply) recommendations?
Post by: Patrick on September 10, 2011, 01:32:47 PM
I just had a very bad experience with my r4's batteries dying in the middle of a recording.  Basically, I lost the files since the r4 didn't save the data before shutting down the hard drive.  This apparently has never happened before, because I've never lost a recording in the 4.5 years of running the r4.

I am going to be doing some more recording for hire in the next few weeks and my company has agreed to purchase a Uninterruptible Power Supply for the recording rig. It needs to be small and cheap, I saw some online that essentially looked like power strips which is what I would prefer rather than a tower unit.  I'm not looking for hours of run time after a potential power failure, but enough to stop the deck and save my data.  Honestly, less than 10 minutes of runtime would probably be fine for our purposes.

Thanks!
Title: Re: Small UPS (power supply) recommendations?
Post by: H₂O on September 10, 2011, 07:55:31 PM
UPS' are typically associated with AC power not DC power.  Will you have access to AC?
Title: Re: Small UPS (power supply) recommendations?
Post by: Patrick on September 10, 2011, 08:30:41 PM
UPS' are typically associated with AC power not DC power.  Will you have access to AC?

yes, I forgot to mention this.  The UPS will be powering my R4, hard drives, and possibly a laptop or two.  This is for paid location recordings, not 'audience taping' so to speak.   
Title: Re: Small UPS (power supply) recommendations?
Post by: H₂O on September 10, 2011, 08:45:51 PM
Are you expecting a brown out?  How stable is the power in the area?  Would the PA/house loose power and thus loose amplification if power was lost, or is it all acoustic/ambient?


Title: Re: Small UPS (power supply) recommendations?
Post by: Patrick on September 10, 2011, 09:24:16 PM
Are you expecting a brown out?  How stable is the power in the area?  Would the PA/house loose power and thus loose amplification if power was lost, or is it all acoustic/ambient?

I'm expecting all of these things and more.  :P  These would be amplified events but I cant lost another recording due to a power issue.  it's a potential loss of money over something easily prevented.
Title: Re: Small UPS (power supply) recommendations?
Post by: rastasean on September 11, 2011, 11:11:11 AM
Most UPS' that I know don't run for hours at a time...generally long enough to power everything off and unplug the equipment...10-30 minutes depending on the load.

I think APC is the top brand and I imagine that's because they do a lot of marketing and been around awhile. This UPS selector: http://www.apc.com/tools/ups_selector/index.cfm looks pretty handy.

The UPS I have is an APC 1250 and I got it from an estate sale about a month ago. Its working very well but its a tower looking one and I imagine this kind is now discontinued. Even though it is an older one, it has an LCD that tells me things like the approximate runtime and input load. 
Title: Re: Small UPS (power supply) recommendations?
Post by: kirk97132 on September 11, 2011, 12:56:24 PM
As the Shop Mgr at a lighting production company we used UPS in order to allow shutdown of computer driven light boards so that all the programing would not be lost in the event of the power going ouot (or being disconnected) to get a 30 minute window the UPS was a 4 unit high rack mount that weighed about 75 LBS.  The small lightweight ones give you a very small amount of time to do a shutdown. 
Title: Re: Small UPS (power supply) recommendations?
Post by: DigiGal on September 11, 2011, 01:04:27 PM
These would be amplified events but I cant lost another recording due to a power issue.  it's a potential loss of money over something easily prevented.

If the PA loses power what will you be recording?  You would just need UPS with enough capacity to handle all your connected gear for a short time to prevent a lost recording.  If the venue has a backup generator it still takes time for that to get up to speed and then for power to transfer over to it.
Title: Re: Small UPS (power supply) recommendations?
Post by: Patrick on September 11, 2011, 04:37:26 PM
These would be amplified events but I cant lost another recording due to a power issue.  it's a potential loss of money over something easily prevented.

If the PA loses power what will you be recording?  You would just need UPS with enough capacity to handle all your connected gear for a short time to prevent a lost recording.  If the venue has a backup generator it still takes time for that to get up to speed and then for power to transfer over to it.

Honestly, I don't really care about the PA in this situation... but if the power goes out, a drunk patron trips over a taped down power cable, an engineer accidentally unplugs my power source, or a million other accidents that are bound to happen during a show....  I lose my recording and potentially future recording gigs.  All I need is a UPS that goes between house power and my recording deck, preamps, and hard drives, so thet I'll have enough time to stop the deck and save my recording. 

Thanks Kirk and rastasean for the info!
Title: Re: Small UPS (power supply) recommendations?
Post by: ScoobieKW on September 11, 2011, 05:04:28 PM
I'd set up an power budget. How much do your recording devices, preamps, and external drives draw? That times time gives you your size requirements of your ups.

Remember, by their nature laptops have a built in UPS, the battery.

APC has this calculator. Most of your gear will use the misc device category.

Refurb units here are a good value.
http://www.uninterruptiblesolutions.com/smartups-rackmount-c-12.html?zenid=bho3h1064g5p00prn3ie8v8v32
Title: Re: Small UPS (power supply) recommendations?
Post by: Lil Kim Jong-Il on September 11, 2011, 06:43:00 PM
R4, hard drives, and possibly a laptop or two

All these can be driven from an external DC source.  Why not use external high capacity batteries so that you are not dependent on any power source outside of your field kit? No one can unplug you and if you really expect issues like drunken patrons, the mobility of an untethered rig is something that might be useful.
Title: Re: Small UPS (power supply) recommendations?
Post by: Fried Chicken Boy on September 11, 2011, 10:29:07 PM
R4, hard drives, and possibly a laptop or two

All these can be driven from an external DC source.  Why not use external high capacity batteries so that you are not dependent on any power source outside of your field kit? No one can unplug you and if you really expect issues like drunken patrons, the mobility of an untethered rig is something that might be useful.

That's pretty much what I was thinking, too.
Title: Re: Small UPS (power supply) recommendations?
Post by: Patrick on September 12, 2011, 08:44:28 PM
R4, hard drives, and possibly a laptop or two

All these can be driven from an external DC source.  Why not use external high capacity batteries so that you are not dependent on any power source outside of your field kit? No one can unplug you and if you really expect issues like drunken patrons, the mobility of an untethered rig is something that might be useful.

I have a 2>1 battery cable for my R4 that a board member made for me.  I had the thought of using 1 leg of the cable for the AC adapter, and the other leg as a DVD battery backup.  I already enjoy the option of hotswapping batteries and I don't see why running two separate power supplies would be an issue.  Can anyone make an argument against doing this?
Title: Re: Small UPS (power supply) recommendations?
Post by: Lil Kim Jong-Il on September 12, 2011, 11:04:24 PM

If the AC adapter produces a DC voltage suited to both the external battery and the device, you could run them in parallel.  However, if you lose AC and draw battery power for long enough to drain the battery, your AC adapter will need to supply enough current to both drive the recorder and supply the charge current of the battery. If you over tax the AC adapter and it was designed properly, it should current limit or just shut down. If it isn't designed with those protections it might fail in a way that produces smoke and that isn't going to make your client happy. I would definitely test the fail over to battery and subsequent charging before heading into the field.