Test Equipment Anonymous (TEA) group therapy thread

[BU508A]

You may NOT
use 'light Appliance power cord' type cable and affix it by any means to the wall or structure
use single wires in conduits anymore

All the cables are cemented in the walls. My plan was to use a single 2,5mm² cable, grab the live from the next plug and hide it between parquet and walls, there is about 10mm space there. Of course I will protect it inside a 15cm plastic cable holder/rail from the plug down to the parquet

If I just need the live, why I need a three wires cable (PE, N, L)?

Because it will be the right thing to do. I would use a NYM 3x 1,5mm² from a circuit which is dedicated for socket-outlets. Probably I'd use something like a Thealit Brüstungskanal. Example:


A single wire which is life with 230V~ is a no-go!

[Zucca]

Thanks for the inputs.

1) It will be protected in plastic isolation like this:



Must be the cable itself double isolated also inside this?

If not inside that, the cable will be inside the wall and not accessible by normal humans.

When you run a live in anything other than earthed metal containment, you MUST use a cable with an integral CPC (this applies to fixed wiring, not flexes). In practice this is normally 1.5mm² for single brown and earth, can't say as I've seen bigger.

If you're running it in anything other than earthed metal containment, it must also be double insulated.

Usually it's a good idea to have the neutral along for the ride, to avoid swapping neutrals between circuits by accident, as this will affect the performance of the safety devices in your distribution board/consumer unit..[/color][/b]

2) All neutral wires are blue and live wires are brown. Thank God it is like this is also in this apartment. I will pick a 2,5mm² brown wire for this patch. If you swap a blue wire with a brown one.. well 

3) The donor plug and the plug to be patch are behind the same fuse.

I still can't imagine a dangerous situation coming up from this patch, anyway I am here to learn.

[capt bullshot]

Thanks for the inputs.

1) It will be protected in plastic isolation like this:



Must be the cable itself double isolated also inside this?

If not inside that, the cable will be inside the wall and not accessible by normal humans.

When you run a live in anything other than earthed metal containment, you MUST use a cable with an integral CPC (this applies to fixed wiring, not flexes). In practice this is normally 1.5mm² for single brown and earth, can't say as I've seen bigger.

If you're running it in anything other than earthed metal containment, it must also be double insulated.

Usually it's a good idea to have the neutral along for the ride, to avoid swapping neutrals between circuits by accident, as this will affect the performance of the safety devices in your distribution board/consumer unit..[/color][/b]

2) All neutral wires are blue and live wires are brown. Thank God it is like this is also in this apartment. I will pick a 2,5mm² brown wire for this patch. If you swap a blue wire with a brown one.. well 

3) The donor plug and the plug to be patch are behind the same fuse.

I still can't imagine a dangerous situation coming up from this patch, anyway I am here to learn.

Preface: I don't care if it is allowed or not (it isn't here). But - for a proper electrical circuit, it is generally advised to have the return path close to the forward path (say L and N in the same cable). Don't open loops for your circuit. So I wouldn't make that patch this way, since it will open a loop. Just based on physics and general electric rules to avoid confusion and interference. So I'd run a proper three conductor cable to the next available outlet (3x 1.5mm^2), and just don't use the present wires anymore. Or try to fix it somewhere else (maybe there's a junction box available where you could fix it).
Running a single L wire from one wall socket to another one is a no-go, regardless of what the standards say.

[Specmaster]

You may NOT
use 'light Appliance power cord' type cable and affix it by any means to the wall or structure
use single wires in conduits anymore

All the cables are cemented in the walls. My plan was to use a single 2,5mm² cable, grab the live from the next plug and hide it between parquet and walls, there is about 10mm space there. Of course I will protect it inside a 15cm plastic cable holder/rail from the plug down to the parquet

If I just need the live, why I need a three wires cable (PE, N, L)?

Because it will be the right thing to do. I would use a NYM 3x 1,5mm² from a circuit which is dedicated for socket-outlets. Probably I'd use something like a Thealit Brüstungskanal. Example:


A single wire which is life with 230V~ is a no-go!

Correct, a single wire, will dependant on the current flowing setup eddy currents in the other cables and metal casings unless the neutral wire is also run along side it. These eddy currents have been known to cause problems in the past.

[Zucca]

Now it makes sense, thanks!

EDIT: Anyway in a three switch light system the live and the neutral are very far away, but it just a light so not too much current flowing in it... anyway with LED stuff it could generate uneven load/spikes during the 50Hz period time and that's why sometime we get some interferences when the LED lights are on. I suppose. Interesting.

[AVGresponding]

Thanks for the inputs.

1) It will be protected in plastic isolation like this:



Must be the cable itself double isolated also inside this?

If not inside that, the cable will be inside the wall and not accessible by normal humans.

When you run a live in anything other than earthed metal containment, you MUST use a cable with an integral CPC (this applies to fixed wiring, not flexes). In practice this is normally 1.5mm² for single brown and earth, can't say as I've seen bigger.

If you're running it in anything other than earthed metal containment, it must also be double insulated.

Usually it's a good idea to have the neutral along for the ride, to avoid swapping neutrals between circuits by accident, as this will affect the performance of the safety devices in your distribution board/consumer unit..[/color][/b]

2) All neutral wires are blue and live wires are brown. Thank God it is like this is also in this apartment. I will pick a 2,5mm² brown wire for this patch. If you swap a blue wire with a brown one.. well 

3) The donor plug and the plug to be patch are behind the same fuse.

I still can't imagine a dangerous situation coming up from this patch, anyway I am here to learn.

Yes, it must still be double insulated.

When the cable is in the wall, it should be protected also by either conduit, if it's a drywall, or conduit/capping if it's to be plastered over (personally I'd rather use conduit than capping, even though it means a deeper chase, because it will make any future alterations easier).

The only time you may use single insulated wires is if they are contained in earthed metal conduit or trunking.


EDIT: To clear up some apparent confusion; the term "singles" does not mean a live wire all on its lonesome in a tube. It means single insulated, single conductor. When you're using these to supply sockets, for instance, for each circuit you use a brown (line), blue (neutral), and green/yellow (earth).
Previous regulations allow for the sole CPC to be the conduit/trunking, but that's no longer the case, and rightly so, as corrosion invariably degrades the quality of the connection in this system.

Eddy currents are a serious consideration, even to the point that it is not permitted for line/s and neutral in a circuit to pass through different holes in a metal casing.

While you (should) never see physical separation of the line/neutral routing in a power circuit, it's not unusual to see it in a lighting circuit.

[mnementh]

@ Zucca: As important as anything to remember is this; electrical code exists not only for YOU, but for the guy who comes AFTER you and has to try and fix it. Now imagine 20-30 years down the road, the next guy comes behind you and has to figure out where the eff that one wire goes... and WHY it wasn't wired right in the first place. Then he's going to spend an afternoon just like YOU did.

mnem
*juicy*

[Zucca]

Sure Dragon, I would have reverted my red neck patch before leaving that boat.
I did the same when I was living in USA. I patched a 220VAC plug for my TEA 220VAC EU Gear.

Before leaving the relocation company guys were looking at me with strange eyes while I was working with cables at the main electrical panel..... in an empty apartment.

 

[drussell]

When you run a live in anything other than earthed metal containment, you MUST use a cable with an integral CPC

Pardon my ignorance, but what does CPC refer to in this context?

[Cerebus]

When you run a live in anything other than earthed metal containment, you MUST use a cable with an integral CPC

Pardon my ignorance, but what does CPC refer to in this context?

Circuit Protective Conductor (i.e. Earth, but an earth that is only used for protection in the case of a fault)

[Cubdriver]

When you run a live in anything other than earthed metal containment, you MUST use a cable with an integral CPC

Pardon my ignorance, but what does CPC refer to in this context?

Circuit Protective Conductor (i.e. Earth, but an earth that is only used for protection in the case of a fault)

Ahh, ok.  Here in the U.S. at least, in electrical mains work I've commonly heard/seen that referred to as PE (Protective Earth).  We need a decoder ring for all of our different terms, abbreviations and acronyms!

-Pat

[AVGresponding]

When you run a live in anything other than earthed metal containment, you MUST use a cable with an integral CPC

Pardon my ignorance, but what does CPC refer to in this context?

Circuit Protective Conductor (i.e. Earth, but an earth that is only used for protection in the case of a fault)

Ahh, ok.  Here in the U.S. at least, in electrical mains work I've commonly heard/seen that referred to as PE (Protective Earth).  We need a decoder ring for all of our different terms, abbreviations and acronyms!

-Pat

My bad, I should have expanded the acronym. 


DHL just delivered my Rapid order from yesterday, now just waiting for a couple of packages from RS that should have been here yesterday, thanks PorcleFarce   

Included in my Rapid order are 400 0R68 5W wirewound resistors, from the clearance bin, £12.40 + vodka and tonic, bargain!
They're gonna make a nice load bank, forced air cooled ofc.   

[mnementh]

Sure Dragon, I would have reverted my red neck patch before leaving that boat.
I did the same when I was living in USA. I patched a 220VAC plug for my TEA 220VAC EU Gear.

Before leaving the relocation company guys were looking at me with strange eyes while I was working with cables at the main electrical panel..... in an empty apartment.

 

I understand... but the code doesn't recognize your INTENT to "unfuckerize" the wiring (even though it was already fuckerized before you got there) before you leave; while weird folks like you and I WOULD fix it before we left, this attitude protects you and others in case of:

1) Liability if there's a fire (and the investigator notices your bodge) for any reason; the fire doesn't have to be in any way related to your bodge for it to receive the blame. 

2) You move out and forget "that one bodge wire" or have to leave in a hurry and don't have time.

3) You step out in front of a bus (or COVID) and CAN'T unfuckerize things.
4) Probably a dozen even more dire circumstances that I can't think of at the moment.   

Cheers, mate. 

mnem
 

[capt bullshot]

Now it makes sense, thanks!

EDIT: Anyway in a three switch light system the live and the neutral are very far away, but it just a light so not too much current flowing in it... anyway with LED stuff it could generate uneven load/spikes during the 50Hz period time and that's why sometime we get some interferences when the LED lights are on. I suppose. Interesting.

Depends. If done properly, the physical layer would not look like your schematic, but would involve small loops only. But from experience, one can find almost anything in real ...

BTW
A (to at least  some people) well know example of interference by loops (even DC here) are the Strassenbahn (Tram) in major cities. Historically, they run on 600V DC on their overhead lines, and from the transformer / rectifier substation only live side runs through distribution wires to the overhead lines. The return path is somewhere else. For the good ol' CRT colour TVs this sometimes caused discolouring effects, e.g. when such a feeder cable run along the pavement in front of your house, even though there's no tram in your street.

[Cubdriver]

When you run a live in anything other than earthed metal containment, you MUST use a cable with an integral CPC

Pardon my ignorance, but what does CPC refer to in this context?

Circuit Protective Conductor (i.e. Earth, but an earth that is only used for protection in the case of a fault)

Ahh, ok.  Here in the U.S. at least, in electrical mains work I've commonly heard/seen that referred to as PE (Protective Earth).  We need a decoder ring for all of our different terms, abbreviations and acronyms!

-Pat

My bad, I should have expanded the acronym. 


DHL just delivered my Rapid order from yesterday, now just waiting for a couple of packages from RS that should have been here yesterday, thanks PorcleFarce   

Included in my Rapid order are 400 0R68 5W wirewound resistors, from the clearance bin, £12.40 + vodka and tonic, bargain!
They're gonna make a nice load bank, forced air cooled ofc.   

No worries - I think we all do it occasionally.  Terms we've known and used for years are ingrained, and we are inclined to use them without remembering that they in fact ARE specialized bits of knowledge that others might not be familiar with, or that their meanings may be context dependent.  For instance, ARM in the financial world here in the U.S. stands for "Adjustable Rate Mortgage"; a type of home loan where the interest rate is pegged to the prime interest rate and can vary with it over time.  ARM in the electronics world is Advanced RISC Machine, denoting a processor architecture.  I've heard it for years applied to mortgages, so that's the first place my brain goes when I hear the term in an electronics setting, and it always makes me pause for a moment until I remember Advanced RISC Machine rather than the adjustable rate mortgage meaning that initially pops to mind when hearing that particular sequence of letters.

-Pat

[med6753]

Here's a term everyone will recognize. Bored.

Here's another term everyone will recognize. Ebay.


Someone come hide my wallet.   

[AVGresponding]

ProlapseFeces ParcelForce just delivered my RS stuff a short while ago.
Now I have some 6kV rated wire, just need some Corona Dope type stuff, and the fun can begin!   

The cheapy-cheap 2.5mm² silicone insulated will repair my PAT machina, and there will be plenty left for high current test leads.

Here's a term everyone will recognize. Bored.

Here's another term everyone will recognize. Ebay.


Someone come hide my wallet.   

Hah, we're more likely to link you things to spend your money on than hide your wallet!

[med6753]

ProlapseFeces ParcelForce just delivered my RS stuff a short while ago.
Now I have some 6kV rated wire, just need some Corona Dope type stuff, and the fun can begin!   

The cheapy-cheap 2.5mm² silicone insulated will repair my PAT machina, and there will be plenty left for high current test leads.

Hey, did you get the probes? 

[AVGresponding]

Gah... nope.

I didn't read the (poorly handwritten) sign properly on Wednesday morning.

As well as being closed Wednesdays, they are only open from 7am to 9am on other days, instead of 7am to 1pm, so I was too late today at 10am.   


EDIT: I ordered some of this for sealing the angry pixies away:  https://www.ebay.co.uk/itm/BLACK-AIR-DRYING-VARNISH-TRANSFORMER-SOLONOID-INSULATING-VARNISH-100ml/141191482141

[Cerebus]

Been crimping some cables to fit a 'hard metric' socket to go onto a header on a Trimble GPS board I have.

I'm not saying that there are small, but those are grains of rice in the photo (which is fuzzy because getting close enough to fill even 1/4 the frame was beyond the macro capabilities of my lens and I couldn't be buggered to set it up better).

[McBryce]

Wow, where did you find such huge rice grains??

McBryce.

[Cerebus]

Wow, where did you find such huge rice grains??

McBryce.

Travel restrictions be damned, I'm coming to Germany and crimping bits of you! 

[McBryce]

Wow, where did you find such huge rice grains??

McBryce.

Travel restrictions be damned, I'm coming to Germany and crimping bits of you! 

Bring the rice, we're making Sushi tonight.

McBryce.

[Cubdriver]

Here's a term everyone will recognize. Bored.

Here's another term everyone will recognize. Ebay.


Someone come hide my wallet.   

Ok, but there will be a 'small' handling fee for doing so.  <opens eBuy while gleefully rubbing hands together>  On the bright side, your wallet will be lighter and easier to carry upon return.

 

-Pat

[bd139]

Here's a term everyone will recognize. Bored.

Here's another term everyone will recognize. Ebay.


Someone come hide my wallet.   

Been there. Now at the stage: Regret.

Fucking HP desktop fucked up mess of a bios. Grr.