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Universal power supply safety question

hello there - traveling to europe and i'm a musician. all my gear is 110-240 dual power but as i have about 6 pieces of gear - i'm wondering if one or two of these Universal power strips would be safe to use and swap out the respective plug adapter from country to country.

https://www.amazon.com/Yubi-Power-Universal-100-250V-Protector/dp/B00UK706NE/ref=sr_1_1?ie=UTF8&qid=1504546935&sr=8-1-spons&keywords=universal+power+strip&psc=1

or

https://www.amazon.com/dp/B00N13DC9O/ref=psdc_10967801_t1_B00UK706NE

thank you!

Posted by
32220 posts

studio,

Both of those products appear to be designed for "worldwide" use, so should work fine either at home or in Europe. I only took a brief look at the websites you linked, so didn't notice which plugs these are provided with.

One point to note is that although the Power Bars have a fairly high capacity, there may be limitations in the outlets these are connected to, due to the fact that building wiring doesn't use "branch circuits" as we do in North America. Some outlets (ie: the U.K.) are fused, so your gear may draw more current than the outlet is capable of supplying. Some Plug Adaptors may also have limitations on the current they're rated to handle.

As you'll be using the Power Bars with a variety of equipment, I'd suggest using only grounding type Plug Adaptors. Depending on which countries you're travelling in, you'll probably require several Adaptors. Grounding in some countries on the continent is provided by grounding "ears", while in others by a protruding ground pin. The grounding Adaptors for Switzerland and Italy are unique to those countries and not interchangeable.

Posted by
10 posts

Hi ken
Thank you for such a helpful reply. Should I have any concern about harming my gear if it pulls too much in the UK? Would it be more advisable to buy individual adapters for each piece of equipment? (Really trying to avoid having to carry around a heavy step down transformer.) All the gear I use has been made in the last few years.
Thanks!

Posted by
8889 posts

Studio, both those power strip have "Schuko" plugs, so they would plug in directly in most European countries, but not in Italy, Switzerland or UK, you would need further converter plugs for those countries.

The first one says 3750 Watts, 3750 ÷ 240 = 15 Amps. The second one says "10 amp circuit breaker". So you are legal for the sockets in all countries. If 10A is enough I would go for the one with the circuit breaker, a nice safety measure.
But, what does your equipment draw? Hopefully not more than 10A per power strip.
Sockets are usually limited to 13-15A. If you need 2 strips, make sure you plug them into two different sockets, not both into the same socket.

P.S. outlets in the UK are not normally fused. But in a music venue they may be stop musicians overloading them.

Posted by
10 posts

Great - thank you Chris. I'll double check the amps but yeah I shouldn't be drawing that much and your explanation really clears things up.

Posted by
5333 posts

Ensure that your UK adaptor is compliant with UK regs and includes amongst other things a fuse. Easiest to buy in the UK as too much sold elsewhere is sub-standard, fake or both.

The second one you link to appears to not meet UK regs as the live/neutral on the sockets appear not to be shuttered although the picture isn't completely clear.

Posted by
5836 posts

If you need 2 strips, make sure you plug them into two different sockets, not both into the same socket.

If both of your power strips are loaded to full power you need to plug them into different circuits which would be difficult to determine without the room's wiring schematic. Each circuit is protected by its circuit breaker (fuse). The circuit will likely include multiple sockets and could even include a room's overhead light. Hopefully the sockets serving the hair dryer are on a different circuit.

Posted by
10 posts

Thanks for the info. Do you think it's just safer to use individual adapters for each piece of equipment in that case?

Posted by
5836 posts

Just don't turn on all six devices at the same time.

Posted by
32220 posts

studio,

Using individual Plug Adaptors for each piece of equipment is not going to achieve anything as they won't change the overall total current draw. The Power Bars already have outlets designed to accept North American plugs so using separate Plug Adaptors is not necessary.

Buying a step down transformer will also not improve the situation, and will just add an unnecessary and heavy piece of gear to haul around Europe. The current draw of your musical gear will be less at 240 VAC than it is at 120 VAC (roughly half as much at 240).

Just to confirm, is ALL the stuff you'll be travelling with designed for multi-voltage operation, including not only music gear but also personal stuff like cell phones, camera chargers, hair appliances, etc.? That needs to be verified.

Posted by
5836 posts

You will need to add up the current (amp) draw of each piece of equipment and keep the total under the rated capacity of each power strip and each circuit. That would be conservative in that you are note likely to peak each device. Presumably the stage electrician would be able to tell you the current limit of each circuit you connect into. And if you are wrong the circuit breaker will trip,

Posted by
10 posts

Hi thank you everyone - yes everything i have is up to date and dual :) The only time I'll be using all the equipment is performance - otherwise the random phone charge at hotels etc won't be an issue.

Do i add up the amp IN or amp OUT on the adapter?

Posted by
8889 posts

Do i add up the amp IN or amp OUT on the adapter?

It should be the same. Electricity flows in circles, what goes in must come out, unless you have a short circuit to something metal!
Perhaps you are confusing Amps with Watts, i.e. power.
Watts = Volts x Amps. The Watts in will come out as audio (Watts out of the speakers), and heat (your gear gets hot, especially the amplifiers).

Posted by
32220 posts

studio,

You should add the current (amps) that the device draws at 230 VAC. The difference can be seen on this nameplate label......

https://eagle07.smugmug.com/Family/Travel-Information/i-cqCgFmR/A

Not all nameplate labels will be this detailed, but this should provide an idea on what to look for.

"The Watts in will come out as audio (Watts out of the speakers)"

Just to clarify, with audio amps and speakers the power delivered to the speakers will be slightly less than the power delivered from the power point, due to "losses" in various parts of the circuits. I can provide an example if you're interested.

In any case, the important criteria in this application is the current drawn from the power point (outlet). If you'll be performing in venues that are designed for modern bands, I suspect they will have a more robust power system. In order to provide maximum capacity for your gear, you might want to buy the first power bar that you linked (the 15 amp model).

Posted by
10 posts

Hi - i'm still confused by one thing - when calculating up to 10 or 15 amps - do I read the back of power supply where it says OUTPUT or INPUT? For example using the photo you gave me - the Output lists .7A.
https://eagle07.smugmug.com/Family/Travel-Information/i-cqCgFmR/A
I understand the mathematical formula everyone has given me in computing Amps from Watts and Volts and I understand I cannot draw over a certain amount of electricity from a power outlet. What I'm now trying to take into consideration is a circuit breaker either at 10 or 15 amps on these Universal power strips. So using the above photo as an example is the" .7A "- the amperage that I'm to add with any other devices and their amps? The labels input / output is what confuses me because I have devices that have Amps on both input and output listed. At this point I just want to know how to read the amps and add them together correctly to choose the best option. Thanks.

Posted by
5836 posts

The electrical demand you are putting on the supply side is the "Input". That is the power you are drawing from the circuit. The "Output" is what your converter is sending to the device.

Power P (watts) = Current I (amps) x Voltage V (volts)

Posted by
10 posts

So I add the input amps?
Example my power supply says:
Input: 100-240V 50/60hz 0.8A
The .8A is what I should paying attention to when adding amps make sure I don't trigger the circuit breaker?

Posted by
10 posts

So I add the input amps?
Example my power supply says:
Input: 100-240V 50/60hz 0.8A
The .8A is what I should paying attention to when adding amps make sure I don't trigger the circuit breaker?

Posted by
32909 posts

yup, that's right.

But if you are talking a musician's power amp, 0.8A is mighty low power.

Posted by
32220 posts

Does the nameplate label say anything else? Those spec's are a bit limited, as the current draw should be different between 120 VAC and 240 VAC. What type of amp is it?

Posted by
7360 posts

I suggest that you tell us the input rating on your largest piece of gear. I can't imagine a guitar amp with a wall-wart or "brick" type of power supply. Maybe you are more of an electronic musician? Is some of your gear more "consumer" or "home entertainment" style? Does most of your gear have US parallel blade, two prong plugs?

You won't be able to tell until you get the adaptor strips, but some of those with little flippers that cover the empty slots are kind of flimsy. The other issue is whether the contacts grab your male plugs strongly enough. It's a quality issue. I've found that adaptors that ONLY take USA plugs tend to grip the prongs better - partly because they don't have to suit so many different shapes of pin.

Posted by
10 posts

I'm an electronic musician - all my gear is synth or drum machine / sampler based. Meaning no amps.

Ok here's an example of the highest AC adapter:

Input: 100-240 V ~50-60hz 1.4A Max
Output: 15V (DC symbol) 4.3A

Posted by
5836 posts

Input: 100-240 V ~50-60hz 1.4A Max

The maximum amperage of 1.4 Amps would be associated with the 100 volts. You could power about 10 of those devices on a typical North American 15 amp circuit. Exception could be devices that have short spike peaks and a quick reacting breaker.

At 220 volts, you would be drawing about 0.7 amps. That is a pretty minimum draw. Again, have the stage electrician confirm the circuit amperage.

Looks like your device(s) feeds must be feeding into a power amplifier.