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Outlet & Voltage Question
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The Final Dakar
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Jul 1, 2018, 01:23 PM
 
So in my hallway for some reason I have a receptacle that looks like this:


I'd like to use it but obviously I'd need some kind voltage converter. Those aren't easy to find. What I did find was this:
https://www.amazon.com/Ceptics-CTU-1...dp/B01MR9DBRQ/


I don't know anything about USB but my assumption is that its power output might be standard. My question is pretty simple: Would it be safe to plug in something (like, say, an Amazon Echo) into the USB slot or would the damn thing fry it?

I'd obviously not use the outlet on this adapter because its still putting out 240v.
     
subego
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Jul 1, 2018, 02:43 PM
 
Is that an Aussie socket?

Do you have a circuit tester? Is it actually wired at 240? It’s probably not. If it is, that’s a ridiculous code violation.
     
subego
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Jul 1, 2018, 02:49 PM
 
Here’s a standard breaker panel.



Assuming proper wiring, the set of breakers on the right can only get 120. The set of breakers the left can only get 120.

To get 240, the breaker has to be in the middle, like the single one up top, which is the main breaker for my entire apartment.

If you can trip one of your normal (side) breakers and kill that socket, it’s only running 120.

Still, throw a tester on it.
     
reader50
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Jul 1, 2018, 03:15 PM
 
Originally Posted by The Final Dakar View Post
So in my hallway for some reason I have a receptacle that looks like this:
Where is this, what country? It looks like an Aussie plug, but could also be an obsolete US style, pre-NEMA. Likely to be 240v, but could be 120v if it's the obsolete plug. The prong at the bottom could be ground (aussie) or a neutral (which could be used to get 120v against one of the hots).

As USB would be fed by a switched-power-supply circuit, it usually doesn't matter if the source is 120v or 240v. You'll get regulated 5VDC either way. If in doubt, plug in your most worthless USB device to test. Like that co-worker's noise maker. If something goes wrong -- honest mistakes happen.

@subego, it's normal in breaker panels to alternate legs. Left or right column doesn't matter. Instead, any two adjacent locations can be used for a 240v double breaker. ie - the panel is lugged like so:

A
B
A
B
A
B

Where hot legs A and B are used. A 3-phase panel would add a leg C to the rotation.
     
The Final Dakar  (op)
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Jul 1, 2018, 03:16 PM
 
Oh, I'm here in the US. I bought a voltage detector and it did come up 240 (assuming I did it right). I'll take a picture since you guys are in awe.

Edit: I have an old iPod touch or Iphone 4S I can sacrifice to science.
     
subego
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Jul 1, 2018, 03:18 PM
 
To answer your main question though, the adapter says it’s rated to 240, so the USB sockets are all good regardless.
     
subego
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Jul 1, 2018, 03:19 PM
 
Originally Posted by reader50 View Post
Where is this, what country? It looks like an Aussie plug, but could also be an obsolete US style, pre-NEMA. Likely to be 240v, but could be 120v if it's the obsolete plug. The prong at the bottom could be ground (aussie) or a neutral (which could be used to get 120v against one of the hots).

As USB would be fed by a switched-power-supply circuit, it usually doesn't matter if the source is 120v or 240v. You'll get regulated 5VDC either way. If in doubt, plug in your most worthless USB device to test. Like that co-worker's noise maker. If something goes wrong -- honest mistakes happen.

@subego, it's normal in breaker panels to alternate legs. Left or right column doesn't matter. Instead, any two adjacent locations can be used for a 240v double breaker. ie - the panel is lugged like so:

A
B
A
B
A
B

Where hot legs A and B are used. A 3-phase panel would add a leg C to the rotation.
You are correct. My bad. I’m rusty.
     
subego
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Jul 1, 2018, 03:53 PM
 
Originally Posted by The Final Dakar View Post
Oh, I'm here in the US. I bought a voltage detector and it did come up 240 (assuming I did it right). I'll take a picture since you guys are in awe.
I believe you, it’s just like WTF, man?

Freedom runs at 120v.
     
The Final Dakar  (op)
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Jul 1, 2018, 04:21 PM
 
It's a very old place. Half my outlets aren't even grounded.
     
reader50
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Jul 1, 2018, 04:23 PM
 
I'd just as soon have freedom run at 240v. Go to Sears and buy a "5 HP air compressor", and the 5HP part refers to startup surge power. Which is meaningless for such a tool.

A standard 120v/15A socket can only deliver 1800W, approx 2.5 HP. You're getting half the tool you thought you were buying. A heavy duty 120v/20A socket does a little better, approx 3.25 HP. This is why electric pressure washers suck in north america. Not enough muscle.
     
subego
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Jul 1, 2018, 04:24 PM
 
Originally Posted by The Final Dakar View Post
It's a very old place. Half my outlets aren't even grounded.
Well thank god they took the trouble to ground the New Zealand shit.
     
subego
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Jul 1, 2018, 04:34 PM
 
Originally Posted by reader50 View Post
I'd just as soon have freedom run at 240v. Go to Sears and buy a "5 HP air compressor", and the 5HP part refers to startup surge power. Which is meaningless for such a tool.

A standard 120v/15A socket can only deliver 1800W, approx 2.5 HP. You're getting half the tool you thought you were buying. A heavy duty 120v/20A socket does a little better, approx 3.25 HP. This is why electric pressure washers suck in north america. Not enough muscle.
That is the nice thing. That one outlet should be able to run well in excess of 3,000 Watts.
     
The Final Dakar  (op)
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Jul 1, 2018, 09:01 PM
 
OK, thanks. Unfortunately I waited so long to post this the adapter is no longer in stock.
     
reader50
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Jul 1, 2018, 10:57 PM
 
It isn't? Did you try the buying choices link on the page? $40 yes, but with two sellers.

You could also have the socket replaced with a more standard one. Assuming there is a neutral wire in the box, you could have any standard 120v socket installed. Including one of those with USB.
     
Waragainstsleep
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Jul 2, 2018, 05:03 AM
 
That USB adaptor says 5V, 2.1A which is a standard. Got one in my car which does that and my iPhone 6S is fine with it, as was my 5S.
I have plenty of more important things to do, if only I could bring myself to do them....
     
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Jul 2, 2018, 07:59 AM
 
Originally Posted by The Final Dakar View Post
It's a very old place. Half my outlets aren't even grounded.
Have an electrician install a ground fault circuit interrupter in the central.
( Last edited by P; Jul 2, 2018 at 09:23 AM. )
The new Mac Pro has up to 30 MB of cache inside the processor itself. That's more than the HD in my first Mac. Somehow I'm still running out of space.
     
P
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Jul 2, 2018, 09:22 AM
 
Originally Posted by Waragainstsleep View Post
That USB adaptor says 5V, 2.1A which is a standard. Got one in my car which does that and my iPhone 6S is fine with it, as was my 5S.
Beware the marking on those things...

The "standard" (USB 2.0 Battery Charging Supplement) is max 1.8A if you disable the data lines and 1.5A if you keep them active at low bandwidth. The 2.1A and 2.4A levels are Apple-designed non-standard applications of the standard. They made them for the iPad, but a lot of other people have reverse-engineered them and added those charging levels. If the receiving device does not support the higher power level - like a lot of iPhones - they will charge at the top power that they can accept. Since it is still higher than the 1A of the Apple iPhone charger, they charge faster even if it isn't quite twice as fast.

However - a lot of those chargers just plain lie about how much power they can provide. They say 2.1A when they can only handle 1.8, because they need 10W power on the supply side and the rest is conversion losses. The say 2.1A when they can only reach that when using Quick Charge (a Qualcomm proprietary thing that no Apple device supports).

The answer to this insanity is USB 3.0 Power Delivery, but no iOS device supports that - yet.
The new Mac Pro has up to 30 MB of cache inside the processor itself. That's more than the HD in my first Mac. Somehow I'm still running out of space.
     
P
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Jul 2, 2018, 09:30 AM
 
Originally Posted by reader50 View Post
You could also have the socket replaced with a more standard one. Assuming there is a neutral wire in the box, you could have any standard 120v socket installed. Including one of those with USB.
That would only work if the power is supplied by two different phases, both of which are 120 V to the neutral but shifted 180°. I am not familiar with US electric standards, much less obsolete ones, but that seems like a strange way to electrify anything?

And since I'm asking, what frequency is the power? Australian is 50Hz, but US is 60 Hz.
The new Mac Pro has up to 30 MB of cache inside the processor itself. That's more than the HD in my first Mac. Somehow I'm still running out of space.
     
The Final Dakar  (op)
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Jul 2, 2018, 10:25 AM
 
Originally Posted by P View Post
Have an electrician install a ground fault circuit interrupter in the central.
I'll state that I rent this place, so tips for home improvement are futile.
     
reader50
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Jul 2, 2018, 10:49 AM
 
Originally Posted by P View Post
That would only work if the power is supplied by two different phases, both of which are 120 V to the neutral but shifted 180°. I am not familiar with US electric standards, much less obsolete ones, but that seems like a strange way to electrify anything?
US residential power is done with 240v and a transformer center tap neutral. ie - two 120v hot legs 180º apart vs a common neutral.

Most household devices (sockets, lights) use one hot leg and the neutral for 120v. When a 240v appliance is needed (stove, oven, air conditioner, hot tub, etc) both hot legs are brought to that box. Typically with the neutral as well. A grounded (earthed) leg is also delivered to all locations.

The system was designed for safety, nothing is more than 120v against ground. With a full 240v available if it needs to be. Most of the time it isn't, and the two hot legs just supply alternating branch circuits.
     
The Final Dakar  (op)
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Jul 2, 2018, 10:54 AM
 
Originally Posted by reader50 View Post
It isn't? Did you try the buying choices link on the page? $40 yes, but with two sellers.

You could also have the socket replaced with a more standard one. Assuming there is a neutral wire in the box, you could have any standard 120v socket installed. Including one of those with USB.
I'm not paying $40 for a $15 adapter
     
reader50
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Jul 2, 2018, 11:07 AM
 
Have it your way. $13 with free ship.
     
P
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Jul 2, 2018, 11:11 AM
 
Originally Posted by reader50 View Post
US residential power is done with 240v and a transformer center tap neutral. ie - two 120v hot legs 180º apart vs a common neutral.

Most household devices (sockets, lights) use one hot leg and the neutral for 120v. When a 240v appliance is needed (stove, oven, air conditioner, hot tub, etc) both hot legs are brought to that box. Typically with the neutral as well. A grounded (earthed) leg is also delivered to all locations.

The system was designed for safety, nothing is more than 120v against ground. With a full 240v available if it needs to be. Most of the time it isn't, and the two hot legs just supply alternating branch circuits.
Thanks for the lesson. Most EU systems are three 230V lines shifted 120°. Regular household items use one of those phases versus neutral for 230V, while things that require more power use the difference between two of those phases for 400V power. Bathrooms often have 110V outlets, if there are outlets at all. The reason for the phase shift is apparently that it is the most efficient way to design the generator - or it was, in the olden days when they decided this thing. I assumed that the US system was designed on the same principles, but I guess I was wrong.
The new Mac Pro has up to 30 MB of cache inside the processor itself. That's more than the HD in my first Mac. Somehow I'm still running out of space.
     
reader50
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Jul 2, 2018, 11:25 AM
 
Commercial often uses 120/208v, using 3x 120v 120º apart. Most 240v appliances are also rated for 208v use, in case they're used in a business.

Business and industrial also uses 480v 3ø (with or without a neutral) for heavy motor applications.

3ø is the most efficient for power transmission (maximum power per conductor on the pole), but it's also chosen for motor usage. A 3ø motor has substantial starting torque at 0 RPM. Induction motors on single-phase have no torque at 0 RPM and require additional starting circuits. That's why single-phase motors often have start/run capacitors.

The 90º phase shift a capacitor offers is used to fake a 3rd leg for starting torque (start capacitor). Sometimes a smaller cap (run cap) is left in the circuit after startup for improved efficiency. Continuing to supply a fake 3rd leg. This is inferior to a real 3rd leg, because the capacitor does not adjust current supplied vs motor load.

Such a motor has to have the run cap dialed in fairly well to its constant load (a fan motor for example). A single-phase motor with run cap can sometimes overheat when running unloaded, because it's being fed sufficient current on the fake leg, to operate at full load.
     
reader50
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Jul 2, 2018, 12:40 PM
 
I was unaware of the 230 / 400 system. I knew Europe was 230/240v 50Hz, but didn't know how it was generated.

How is the 110v in bathrooms created? Transformer in-house? Or perhaps even transformered by the outlet?
     
Laminar
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Jul 2, 2018, 12:49 PM
 
Originally Posted by reader50 View Post
I was unaware of the 230 / 400 system. I knew Europe was 230/240v 50Hz, but didn't know how it was generated.

How is the 110v in bathrooms created? Transformer in-house? Or perhaps even transformered by the outlet?
When I took my wife to Australia I took my adapters with and figured we'd be fine. I didn't think through all of my electronics being fine taking 240V but her curling iron and hairdrying being extremely specific about 120V. We tripped the breaker in our room within the first half hour of being there. The concierge had a heavy transformer box he gave us that plugged into the 240V and output 120 for appliances that required it.
     
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Jul 2, 2018, 01:24 PM
 
I know about start capacitors for engines - I have replaced them several times (for a wood splitter and for a pump to a pool). When engines stand still for six months, starting them again fries those capacitors sometimes. Replacing the cap is way cheaper than buying new stuff.

Originally Posted by reader50 View Post
I was unaware of the 230 / 400 system. I knew Europe was 230/240v 50Hz, but didn't know how it was generated.

How is the 110v in bathrooms created? Transformer in-house? Or perhaps even transformered by the outlet?
The 110V outlets in bathrooms are no longer standard, but back in the day, there was a transformer in the outlet itself. These days you can have 230V outlets in bathrooms (with certain rules for placement) as long as they’re grounded or double isolated, have GFCI and I think a smallish fuse for the outlet, but I may be wrong on the last point.
The new Mac Pro has up to 30 MB of cache inside the processor itself. That's more than the HD in my first Mac. Somehow I'm still running out of space.
     
The Final Dakar  (op)
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Jul 2, 2018, 02:43 PM
 
Apparently NN was missing a 'voltage chat' thread
     
ghporter
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Jul 2, 2018, 10:01 PM
 
It was definitely needed!

Trivia: aircraft electrical systems are divided into 28VDC and 110V/400Hz systems. Sometimes equipment used 3 phase AC at 400Hz.

Something to note: that 400Hz winds up "leaking" into every audio system that isn't seriously filtered against it. I find it somewhat annoying to listen to cockpit audio because of the 400Hz tone. It is just enough below a "middle" A (440Hz) to sound "wrong" even though my radio technician brain "knows" that 400Hz is correct (along with 1kHz).

Glenn -----OTR/L, MOT, Tx
     
Spheric Harlot
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Jul 3, 2018, 07:36 AM
 
Originally Posted by P View Post
The 110V outlets in bathrooms are no longer standard, but back in the day, there was a transformer in the outlet itself. These days you can have 230V outlets in bathrooms (with certain rules for placement) as long as they’re grounded or double isolated, have GFCI and I think a smallish fuse for the outlet, but I may be wrong on the last point.
Was that a Scando thing?

I've never seen 110V outlets here except in hotel bathrooms. Private bathrooms all had 220V back in the 70s.
     
P
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Jul 3, 2018, 01:53 PM
 
Originally Posted by Spheric Harlot View Post
Was that a Scando thing?

I've never seen 110V outlets here except in hotel bathrooms. Private bathrooms all had 220V back in the 70s.
Probably, yes. I know that bathrooms and outlets are the one area where the electrical systems of Europe all diverge. We eventually allowed them only because people were running extension cords into the bathroom to power their things anyway, and that might even be ungrounded outlets at the time.
The new Mac Pro has up to 30 MB of cache inside the processor itself. That's more than the HD in my first Mac. Somehow I'm still running out of space.
     
subego
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Jul 3, 2018, 03:52 PM
 
I actually experienced what I think was (my first) brownout last night.

Not enough to kill the lights, but it drove my UPSs crazy for 10 minutes.

There was so much noise on the line, my home automation system interpreted some of it as powerline signals, and started turning lights on randomly.
     
subego
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Jul 3, 2018, 04:04 PM
 
My server flipping out...

     
   
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