[bobobio]

Hi,

I have a question for someone who knows about UPS boxes.

I'm currently living in the US and have a few things (DVD Player, Wii...) that require 110V 60Hz input. I'm about to move to Barbados where the mains supply is 110V 50Hz. Notice the change in freq.

I like the idea of getting a UPS anyway, but now need to make sure I can get one that will take 50Hz input freq and give me 60Hz output freq.

I've looked around and found UPS boxes that say they will take 50/60Hz input, but the output is synced to the input, meaning a 50Hz input will give a 50Hz output only. Is this the case for all UPS boxes? I called one company and the girl changed her mind every 2 minutes, so she obviously had no idea.

Anyone got any advice (other than buy a new DVD Player, Wii, etc)?

Thanks,
Karl

also, if you think this would be better suited for a different forum, please point me to it.

[spocksbeard]

I will ask my Dad tomorrow, he has spent the last 15-20 years working for UPS companies so should know what he's talking about!

[bobobio]

That sounds great. He sounds like exactly the kinda guy whose opinion I need. Let me know what he says. Thanks!

[Jason Bourne]

Hi Bobobio

A lagre amout of "simple" electronic equipment such as DVD players don't need any form of frequency conversion because the first thing that happens inside the player is the AC is rectified to DC.

It's usually things like some clocks use the frequency to keep time or equipment with AC motors where there speed is determined by the supply frequecy that have problems.

So there is a fair chance that "most" (he said sticking his neck out) of you kit will work with no problem on 50 Hz

[spocksbeard]

Originally Posted by bobobio

That sounds great. He sounds like exactly the kinda guy whose opinion I need. Let me know what he says. Thanks!

He said "You can get one that will do it, but it has to be able to have the bypass disabled". He recommends trying a company called Bonitas, who are in Kent (not his company btw), and talking it over with them.

Hope this is helpful

[larkone]

Something else to consider is making sure your UPS has enough capacity, as Barbados suffers huge voltage drops at certain times. We have seen our portable sound system just stop sometimes because there just isn't enough voltage to keep it running - usually around mealtimes at weekends.

[bjarvis2785]

what you need is a referred to an an 'online' UPS.
Voltage and Frequency Independent.

These work by taking in the AC voltage, putting it through a rectifier to convert to DC, then the DC is put through an inverter to produce AC output.

You then get a perfect sine wave output, with selectable frequency.

(that's the most basic way of describing an online UPS)

Not all manufacturers UPS can operate as a frequency converter so make sure before you buy!

Also, as said above, don't switch over to a bypass line as this then would put through the raw mains voltage and frequency.
The UPS units that i sell will know that it's operating in frequency conversion mode and will not automatically switch over to bypass (in the case of a UPS fault etc) but you can still manually switch it, so just remember not to

Hope this helps.

[bobobio]

bjarvis,

That does sound like what I need. Thanks for the explanation, it makes perfect sense to me, and now explains why 'regular' UPS systems would just pass the freq straight through.

So I've had a quick search for online UPS units and it seems like they are much more expensive than regular ones. I see a price jump from about $150 to about $550. Does that sounds right to you? Or should I be able to find cheaper online UPS units?



larkone,

Thanks for the input, I'll be sure to get one with more capacity for that reason.