Digital Consoles w/UPS and Generators

Hal Harrison

Hal Harrison

Sophomore
Sep 22, 2011
151
0
16
Greenville, SC
www.harrisonpro.net
Hello all,

My partner and I just finished a long weekend full of shows. We were using 2 Yamaha LS9-32 (1 FOH and 1 MON) each attached to its own APC UPS. All of the audio was being powered using a standard 25kVA generator from United Rentals. We setup and began sound checks around 3PM for several different bands and everything was working great until the 1st opener started. About half way through the first set the FOH LS9 rebooted itself. I thought at first it was just a digital hiccup (although I have never had a problem with the desk doing anything like this before). As soon as the LS9 rebooted, audio once again began passing through the console. Hoping this was just a hiccup, we continued on through the first opener. For the second opener during their first song the LS9 on monitors rebooted as well. Shortly thereafter, the FOH LS9 once again rebooted and within 2 miuntes of coming back up it rebooted again. At this time, it was apparent something was quite wrong. Since it was not an isolated incident (both MON and FOH consoles doing the exact same thing) we figured it was something with the power. The thing was - we have run our LS9s off generators dozens of times with no problems. In an effort to troubleshoot, we let the second opener finish the song they were on and they took a 3 min break so we could quickly check the generator and took out each UPS attached to the LS9s. After that, we didnt have a single issue for the rest of the night or the weekend for that matter. This all of course begs the question, has anyone had any similar experiences with digital desks w/UPS's attached running off a generator?

Interested in your responses,
Hal
 
Re: Digital Consoles w/UPS and Generators

I've had that problem with the APC home/office UPS's before in a computer environment. Sometimes the battery wears out and the whole thing gets glitchy. But more often, the power feed to the UPS dips or jumps in voltage. The lower-end APC units don't correct for voltage changes for you very well. They do great taking over if the power drops completely, but they don't smooth out things very well when the power is just dirty or likely to dip to 100v once in a while. Different equipment handles that dirtiness better and worse -- sounds like your LS9 is sensitive to it.

On my end, I've started using CyberPower UPS systems for both computers and audio FOH. Everywhere I had voltage dip problems with the APC units, the cyberpowe units handled it fine. Their AVR units do a nice job or regulating the voltage even on their low-end models. APC does it well on their high-end models, but I've not found their low end models to do nearly as good a job as the Cyberpower ones. Look at the SmartApp ones for rackmount, or the AVR series for desktop.
 
Re: Digital Consoles w/UPS and Generators

Hal!

Who's this little boy?! Am I in trouble? :)

Hal.png

The best thing in the world is (of course) a 2RU SurgeX UPS.

The cheap things I use are these APC units.

Do not go any cheaper. The reason the APC UPS Pro 700 is so good is that it has a built in voltage regulator. Yamaha consoles do fine with the square waves that UPS mfg's call a "modified sine wave", but it's best to avoid that. Purchasing a non-SurgeX true sine wave UPS is a waste of money. IMO.

My tests on the APC UPS Pro 700 with out-of-the-box settings (which happen to be best and is called "Normal Sensitivity"), show that with an input of 88v-140v, the thing will use it's voltage regulator to give you a true sine wave output of 98v-131v. Go beyond those input voltages and the thing will go to ugly battery mode that still works perfectly on my M7's.
 
Re: Digital Consoles w/UPS and Generators

Langston Holland said:
Hal!

Who's this little boy?! Am I in trouble? :)

The best thing in the world is (of course) a 2RU SurgeX UPS.

The cheap things I use are these APC units.

Do not go any cheaper. The reason the APC UPS Pro 700 is so good is that it has a built in voltage regulator. Yamaha consoles do fine with the square waves that UPS mfg's call a "modified sine wave", but it's best to avoid that. Purchasing a non-SurgeX true sine wave UPS is a waste of money. IMO.

My tests on the APC UPS Pro 700 with out-of-the-box settings (which happen to be best and is called "Normal Sensitivity"), show that with an input of 88v-140v, the thing will use it's voltage regulator to give you a true sine wave output of 98v-131v. Go beyond those input voltages and the thing will go to ugly battery mode that still works perfectly on my M7's.
Click to expand...

Agreed on the SurgeX units. Something worth mentioning about SurgeX is that their customer service is outstanding. If anything connected to a SurgeX unit is damaged during any power issue or problem with the SurgeX unit, they will take care of the damages with pretty much no questions asked.

While I haven't had any interactions with their customer service, I've used the APC units. I don't recall the model, but I'm pretty sure it's the older version of the one Langston recommended. (A few years ago, red backlight on the display.)

Tripplite makes some pretty good products as well. I don't recall the model of the unit I have.

These dealt with a fairly large input voltage fluctuation on a regular basis. These were used to run my 01v96, along with DSPs, and playback computers in an outdoor installation setting. I have had no problems with any UPSs. My customer service experience with SurgeX had to do with a power conditioner/sequencer.
 
Re: Digital Consoles w/UPS and Generators

The ES series doesn't have voltage regulation (AVR). So a generator dipping the voltage is going to get any device that doesn't have a power supply robust enough to handle that. Looks like the Pro series that Langston mentioned does have voltage regulation.

The APC units I'd been using that gave me problems also had the 'BackUPS pro' moniker, but they didn't look like the ones on the current APC site... so there's a reasonable chance the ones I had weren't supposed to have AVR in the first place.
 
Re: Digital Consoles w/UPS and Generators

Lang,

It is going to be tough to attach the ES-350 on the end of my boat anchor chain as the chain is already attached to a M-EQ230, a sonic maximizer and a few 3630s. Since you are in FL I know you are probably always needing an extra boat anchor - want me to send a 3630 or sonic maximizer your way to serve that purpose?
 
Re: Digital Consoles w/UPS and Generators

Hal Harrison said:
The UPS we had on both FOH and MON was the APC Back-ups ES 350 Back-UPS ES - Product Information

Let me know your thoughts on this UPS.

Thanks,
Hal
Click to expand...

Not suitable..... cheap UPS devices like this will cause you grief. They can detect a problem and fail over to battery, quickly draining the battery completely. I've experimented with several UPS devices on generators, and that particular APC line was really useless and unhappy connected to a couple of different generators I tried it on. They are useful as a battery backup for a home computer, and not much else.

As has been mentioned, look for voltage regulation, and buy way more battery capacity than you need (within your tolerance for added weight)
 
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