Live and neutral pins of Ultra

Chaplyga

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My friends. Is it important which one pin of the power connector of Ultra will be the phase and which one will be neutral?
 

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This very early morning, with eyes not really open, I have written a very long sermon about correct phases as answer, only to notice a bit later that it is the in Germany often so called Euro Stecker/Kupplung. Deleted with shame 🤷🏻‍♂️
 
My friends. Is it important which one pin of the power connector of Ultra will be the phase and which one will be neutral?
There's always just an alternating voltage between both pins and since there is nor further ground as a reference it doesn't matter which is which. Signal ground is not connected to either pin but free floating.

These so called Class II devices (with no safety earth) must provide isolation of the case to protect users from electric shocks. Neither of the power pins must be connected to any part reachable by the user.

You can still try and revert the polarity of the plug to see if there are any unexpected secondary effects, but no matter what you do, the device is safe either way.
 
This very early morning, with eyes not really open, I have written a very long sermon about correct phases as answer, only to notice a bit later that it is the in Germany often so called Euro Stecker/Kupplung. Deleted with shame 🤷🏻‍♂️
That’s why I try to resist posting an hour before bedtime or an hour after waking up (I don’t always succeed) - my brain is in slow motion then…
 
FYI, there are non-polarized (Type A) and polarized (Type B) plugs. Type A are more common, but Type B do exist. It seems like Wiim just uses Type A.

Here is a type B plug.

View attachment 22916
Yep, important note. Type B won't fit any WiiM equipment.

It looks like Type B ist primarily common in the US, Japan and Great Britain. I haven't seen one in my whole life.
 
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I've got one of those Type B in a box somewhere. Not sure what it was ever used for, but I'm one of those "It might come in useful someday" people.

I'm in the UK.
 
Some background.

In many 2 wire plugs used in the US, one blade is larger than the other with matching small and large holes in the receptacle. That insures that the plug only goes in one way and that the hot is always connected to the hot and the neutral is always connected to the neutral. Since the neutral is always connected to ground back in the electrical panel, this guarantees a ground is available in the device, although a separate independent ground wire provides better protection. The C7 polarized plug is just another example of this type of connection. Older plugs often have blades of the same size but those have generally been phased out in favor of 2 different sized blade plugs in devices that draw significant current. The additional of an actual ground wire in 3 wire plugs just provides a separate independent path to the earth ground.


More fun reading :


With 120 volts systems there is 240 volts coming into the electrical panel on 2 hot wires, 1 neutral and 1 ground. To get 240 volts, you use the 2 hot wires. To get 120 volts you use 1 hot and the neutral. The neutral is actually tied to the ground in the breaker box. With European type 230 volt systems there is just 1 hot wire, along with a neutral and a ground, so 120 volts is not available.
 
Most houses in Europe are fed three different hot wires, each with a 120 degree phase difference to the other two (plus neutral plus safety ground), so 400 V 16 A are usually available when needed.
 
Most houses in Europe are fed three different hot wires, each with a 120 degree phase difference to the other two (plus neutral plus safety ground), so 400 V 16 A are usually available when needed.
Really? Three phase in a home? Is it a mansion?
 
Yes, in kitchens it is absolutely normal.
OK. We once rented a flat where the fuse blew when we used the oven and the electric hob at the same time. Turned out the original oven must have had a gas hob and the landlord had plugged a fully electric oven into the 13A socket. He wasn't happy when we told the agent that it should have a dedicated 32A supply 🤣
 
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