Min/Max Acceptable Voltage

[trunkdog]

Apart from contacting the vendor, is there a way to determine the min / max acceptable voltage for a piece of gear (Soundcraft Ui24R)? Would the internal power supply yield a spec? Bottom line: I’m trying to spec a power conditioner / UPS for my studio. I’m guessing the required params are: Wattage, runtime, voltage fluctuation, fan noise. Any others I should research?

 

[dave9]

The internal PSU would be a primary concern, though the UI24R manual has this:
AC input voltage range 88-265VAC auto sensing
AC frequency 47-63Hz

That's probably all the spec you'd get digging further into the PSU in it. You listed the basics but also getting one that's pure sine wave and online or line-interactive type could be useful. You might also consider the monitoring mechanism, whether wireless, USB or serial connection, whether there's some phone app or PC (vs Mac) app, and if it's any good and of course the cost and availability of batteries, and connected equipment protection warranty.

 

[trunkdog]

Thanks Dave. Is that to say acceptable voltage is 88 to 265? Perhaps the unit has the typical 110 / 220 switch.
Shows how little I understand the topic.
I would have thought a tolerance of somewhere around 5% would be reasonable.
Surely you can't apply / allow that voltage range and expect good performance / reliability.
If memory serves me, the CyberPower unit has built in monitoring and yes, pure sine wave.
I also failed to mention that for my application (recording studio) fan noise is a factor.
Educate me, if you have the time / temperament, please.

 

[Harald Kapp]

I would have thought a tolerance of somewhere around 5% would be reasonable.

MOre like +1 10 % for a classic transformer based PSU.
Modern PSUs, however, very often - if not typically - come as so called wide-range power supplies that accept input voltages in the range 88-265V (AC), 50 Hz or 60 Hz nominal).

Surely you can't apply / allow that voltage range and expect good performance / reliability.

You can. A modern switch mode PSU, if built correctly, can be more efficient than a classic transformer based one. See e.g. the efficiency standards for PC power supplies.

getting one that's pure sine wave

Might be a good idea in an audio environment to minimize noise.

for my application (recording studio) fan noise is a factor.

This is a parameter you'll have to look up in the manual/specs of the candidate UPS or find it in online reviews of the same. An alternative is to place the UPS in a separate room where noise is no concern.

 

[dave9]

Yes acceptable range is listed as 88-265V. Since it reads auto sensing it is likely to just be a switchmode PSU with that wide an input range, not a voltage doubler circuit and switch to that mode.

Yes you should be able to use within that range and expect fairly equal performance, with a caveat. At any/every input voltage, you may have SMPS noise because they went with this more efficient PSU design over a linear one, though this is the state of things today. If you find its performance acceptable then I'd just ignore this factor.

I can't tell you which models have the least fan noise, but I can tell you that if you only load the UPS to a fraction of its rating, you could replace the stock fan with one having lower RPM or put a resistor in series on the fan lead to slow it down, or get fancier still and put some kind of thermal speed control on it. "Maybe" the UPS does this, I have never had a cause to look into that. The other option is locate the UPS further away or even in a different room.

Edit: Heh, Harald beat me to most of the above info.

 

[trunkdog]

Again, thanks for the response and education Harald. Re: Fan Noise; yes, manual consulted. I just never thought to consult Soundcraft for voltages as the manual is in general poorly constructed. Placing the UPS in another (mechanical) adjoining room is my likely route, along with other heat generating gear. Am I correct / wise in sourcing a single piece of gear to handle voltage anomalies, surges, spikes, “power conditioning” (whatever that is; I’m assuming the pure sine wave output) and battery backup? It just seems to me that the typical Furman units I’ve raised the hood on lack any substantive parts. CyberPower engineers tell me they offer several models to fill my application. TIA - Barry

 

[trunkdog]

After consulting with the CyberPower engineers tomorrow and finalizing my selection is it proper netiquette to link to this post at the Ui24R facebook usersgroup for edification of any interested parties there?

 

[Harald Kapp]

Am I correct / wise in sourcing a single piece of gear to handle voltage anomalies, surges, spikes, “power conditioning”

A single all-in-one device probably gives the best performance/price ratio unless you are willing to experiment and spend a lot of money. Plus there are the obstacles of testing any random collection of units for performance (I doubt you have the necessary EMC testing equipment ). A reasonable well constructed UPS has at least a built-in filter at the mains front end which will protect your equipment from many sources of disturbance. Then you also have a second level of protection by the power supplies of the audio devices you are powering from the UPS. This should be good for most cases - unless you live in a particularly nasty electromagnetic environment.

is it proper netiquette to link to this post at the Ui24R facebook usersgroup

That's o.k. as long as the link doesn't lead to advertising