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Author: Subject: Need Lab Space Advice - Power at current place can't support all of my equipment
G-Coupled
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[*] posted on 18-12-2019 at 21:02


France is enormous and pretty sparsely populated outside Paris etc. - real strange layout IMO.
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Herr Haber
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[*] posted on 19-12-2019 at 04:36


Quote: Originally posted by RedDwarf  

even with the UK plug which stepping on as DavidJR says can only be equaled by pieces of lego strewn by your children across the carpet like landmines!


The picture reminded me I didnt like walking on those plugs.
Then I thought of Lego bricks aswell !

Genetic memory must exist. It seems everybody on the globe has stepped at least one time on Lego bricks and lived to tell about it.
I recently saw a post on LinkedIn about how much pressure it takes to crush a Lego brick and everybody posting had their own memories of bruised feets.




The spirit of adventure was upon me. Having nitric acid and copper, I had only to learn what the words 'act upon' meant. - Ira Remsen
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DavidJR
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[*] posted on 19-12-2019 at 13:15


They are far worse than lego bricks in my experience...
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[*] posted on 19-12-2019 at 14:12


Quote: Originally posted by DavidJR  
They are far worse than lego bricks in my experience...


Meccano?

Oh, UK electrical plugs, yeah - they always go at angle that maximises the pain by ensuring a shearing action occurs as the skin on your soles applies pressure to the giant prongs.

[Edited on 19-12-2019 by G-Coupled]
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[*] posted on 19-12-2019 at 15:43


Quote: Originally posted by DavidJR  
Quote: Originally posted by morganbw  
(they do not normally expect industrial type of things happening in a dwelling).

I don't think a 3kW space heater or a tumble dryer is an "industrial type of thing".

Quote: Originally posted by j_sum1  

I am surprised that 3kW overloads your circuits. I would talk with an electrician to find out what your options are. Around here, 15 amp circuits @240V are pretty common and higher wattage are not unusual for ovens, sheds and pool equipment.


In the UK, normal sockets are rated for 13A, which at 240v is 3120W. For sockets, we use an unusual "ring main" system, and each ring is usually rated for a total draw of 32A (i.e. 7680W). So, I could plug in two 3kW furnaces side by side and not run into any problems at all.

Higher power stuff like ovens and electric showers do have their own circuits rated appropriately.

Total supply capacity to a house is variable. I just checked and it looks like my house has a 100A main fuse (i.e. max power draw is 24kW). Actually, this is a large house which used to use electric heating, so we have a three phase supply, with each phase fused at 100A (theoretical max 41.5kW) but as far as I am aware we only actually use a single phase now.

Quote: Originally posted by XeonTheMGPony  

then you have places like mine wired by a retard, I had to hunt down ground leakages and ring circuits and other such epic stupidity!

As stated above, this is the normal configuration in the UK and it works very well. It allows higher current for a given wire gauge, and minimizes the effect on other sockets (in terms of voltage drop) of high power loads. That said, there are disadvantages of this approach too - but I disagree that ring circuits are "epic stupidity".

[Edited on 19-12-2019 by DavidJR]


Something to think about is that the OP said he was using 120 volt circuits.
In the USA normal 120 circuits wall plugs are rated at 15 amps, this gives an approximate output of 1800 watts MAXIMUM.
Obviously it is possible to go higher with heaver wiring and higher rated circuit breakers.
The statement about tumble dryers is correct if you are using a 240 volt circuit. The OP specifically stated he was using 120 volt only.

You guys are talking about an entire different electrical systems. USA 120 volt Think please.


[Edited on 12/19/2019 by morganbw]
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[*] posted on 19-12-2019 at 15:50


Some US properties have 240V circuits for clothes driers, HVAC etc., so it's not unheard of.
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[*] posted on 19-12-2019 at 15:56


Quote: Originally posted by DavidJR  
Quote: Originally posted by morganbw  
(they do not normally expect industrial type of things happening in a dwelling).

I don't think a 3kW space heater or a tumble dryer is an "industrial type of thing".

Quote: Originally posted by j_sum1  

I am surprised that 3kW overloads your circuits. I would talk with an electrician to find out what your options are. Around here, 15 amp circuits @240V are pretty common and higher wattage are not unusual for ovens, sheds and pool equipment.


In the UK, normal sockets are rated for 13A, which at 240v is 3120W. For sockets, we use an unusual "ring main" system, and each ring is usually rated for a total draw of 32A (i.e. 7680W). So, I could plug in two 3kW furnaces side by side and not run into any problems at all.

Higher power stuff like ovens and electric showers do have their own circuits rated appropriately.

Total supply capacity to a house is variable. I just checked and it looks like my house has a 100A main fuse (i.e. max power draw is 24kW). Actually, this is a large house which used to use electric heating, so we have a three phase supply, with each phase fused at 100A (theoretical max 41.5kW) but as far as I am aware we only actually use a single phase now.

Quote: Originally posted by XeonTheMGPony  

then you have places like mine wired by a retard, I had to hunt down ground leakages and ring circuits and other such epic stupidity!

As stated above, this is the normal configuration in the UK and it works very well. It allows higher current for a given wire gauge, and minimizes the effect on other sockets (in terms of voltage drop) of high power loads. That said, there are disadvantages of this approach too - but I disagree that ring circuits are "epic stupidity".

[Edited on 19-12-2019 by DavidJR]


In Canada it is very illegal, because if you isolate a breaker then it is being fed by a second = electrocution

Canada and US it is 120/240 nominal, if fed from 3 phase suply will meter out at 208/110 depending whether delta or Y configured, Delta tends to get you the 208. If I recall correctly


[Edited on 20-12-2019 by XeonTheMGPony]
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[*] posted on 19-12-2019 at 17:19


Quote: Originally posted by G-Coupled  
Some US properties have 240V circuits for clothes driers, HVAC etc., so it's not unheard of.


Almost all/probably all of US properties have 240 volt circuits. The OP stated he had only 120 volt circuits.
I live in the US, I have 240 volt circuits, the OP stated he was using 120 volt only.
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[*] posted on 19-12-2019 at 17:33


Quote: Originally posted by XeonTheMGPony  


In Canada it is very illegal, because if you isolate a breaker then it is being fed by a second = electrocution

Canada and US it is 120/240 nominal, if fed from 3 phase suply will meter out at 208/110 depending whether delta or Y configured, Delta tends to get you the 208. If I recall correctly


[Edited on 20-12-2019 by XeonTheMGPony]


The houses I worked on in Florida were fed by single phase 220/240 centre tapped which was earthed. I an reasonable confident the fed was not two phases of a three phase supply as the voltage across the feed was twice the voltage to the centre neutral within a volt or two.

I searched for a diagram but only found a pics of a pole pig but I think they show one phase in and 120/240 out. Apparently this may be just a Florida thing.

pole-pig.JPG - 34kB polepig2.JPG - 47kB

This reminds me of the office I had in Florida next to an Italian restaurant. When one of the three hurricanes that hit the area in just a couple of months it tripped two of the fuses in the three phase to the area. Luckly I was on the working phase but the restaurant was three phase and was closed for two weeks. I saw on the news that all customers now had power back. So I want outside to check if the two blown fuses/links had been replaced on the local pole pig and there was a lineman pushing the last fuse in.

That was a hell of a time. Hard to get food or even petrol for days but I had power at the office but not at home so I lived there for two weeks.

[Edited on 12/20/2019 by wg48temp9]




i am wg48 but not on my usual pc hence the temp handle.

Thank goodness for Fleming and the fungi.
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[*] posted on 19-12-2019 at 19:47


Quote: Originally posted by wg48temp9  
Quote: Originally posted by XeonTheMGPony  


In Canada it is very illegal, because if you isolate a breaker then it is being fed by a second = electrocution

Canada and US it is 120/240 nominal, if fed from 3 phase suply will meter out at 208/110 depending whether delta or Y configured, Delta tends to get you the 208. If I recall correctly

[Edited on 20-12-2019 by XeonTheMGPony]


The houses I worked on in Florida were fed by single phase 220/240 centre tapped which was earthed. I an reasonable confident the fed was not two phases of a three phase supply as the voltage across the feed was twice the voltage to the centre neutral within a volt or two.

I searched for a diagram but only found a pics of a pole pig but I think they show one phase in and 120/240 out. Apparently this may be just a Florida thing.



This reminds me of the office I had in Florida next to an Italian restaurant. When one of the three hurricanes that hit the area in just a couple of months it tripped two of the fuses in the three phase to the area. Luckly I was on the working phase but the restaurant was three phase and was closed for two weeks. I saw on the news that all customers now had power back. So I want outside to check if the two blown fuses/links had been replaced on the local pole pig and there was a lineman pushing the last fuse in.

That was a hell of a time. Hard to get food or even petrol for days but I had power at the office but not at home so I lived there for two weeks.

[Edited on 12/20/2019 by wg48temp9]


yes split phase as it is some times referred to is normal 90% of the time, but allot of commercial buildings will be fed by a 3 phase transformer, usually a center taped Y. or a Delta

https://www.achrnews.com/articles/93448-more-delta-vs-wye-tr...

Single / split phase:

https://en.wikipedia.org/wiki/Split-phase_electric_power

The earth is a common neutral, the high tension goes through the center taped transformer then to earth, then the neutral (Center tap) on the Xformer is all so earthed.

This is why neutral bonding and good grounding are critical if a major fault happens the house can go to pole potential or all loads will go to 240, in the panel Neutral is again bonded to ground

He is being supplied split phase, he's just using one leg of it, if the panel isn't properly load balanced this creats issues along with back feeding from inductive circuits with out power factor correction.

hell some PF correction may just fix his issue if allot of old inductive stuff is running on the panel.

[Edited on 20-12-2019 by XeonTheMGPony]
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