Interesting reason for not using an extension lead with Plug-in Solar

[morqthana]

Eric's scenario was specific to multi-socket extension leads, not extensions in general.

 

[ericmark]

Eric's scenario was specific to multi-socket extension leads, not extensions in general.

Thank you, that is an important point.

In real terms, I don't think I would be testing the pins of the plug, so even if the remained live for 5 minutes, it would not be a problem for me.

But the "and others" added to a competent person when compared with a skilled person, was a question asked with the BS 7671 exam up to 2008, and we have to look at those who don't expect anything to be sold which could be dangerous even where they do unreasonable things.

 

[denso13]

Eric's scenario was specific to multi-socket extension leads, not extensions in general.

I know, but all extension cables are prohibited, therefore, it's a moot point. A theoretical scenario of what could happen if someone ignored the instructions/regulations, nothing more.

 

[SUNRAY]

...

Not sure I see that, though. Do you mean a crossover in the sense of Pin 1 to Pin 2, and Pin 2 to Pin 1? When makers of XLR cables buy in a reel of cable, does the jacket have arrows on it so they know which way to use it?

It is a thing, some 2 core screened cable is made like this:

earth at the top hot & cold below, particularly FST cable (Foil Screened Twin) such as Belden 9501 etc.

Superimposed on an XLR can be a nice match with the hot and cold coinciding with the correct pins:

Or on the wrong end they may need to be crossed over, here shown with hot and cold wires coinciding with the wrong pins:

 

[morqthana]

I know, but all extension cables are prohibited

Actually prohibited, eh?

Hmm....

 

[morqthana]

It is a thing, some 2 core screened cable is made like this:View attachment 423666earth at the top hot & cold below, particularly FST cable (Foil Screened Twin) such as Belden 9501 etc.

Superimposed on an XLR can be a nice match with the hot and cold coinciding with the correct pins: View attachment 423667

Or they may need to be crossed over, here shown with hot and cold wires coinciding with the wrong pins: View attachment 423668

So does that mean if I take a length of such cable, I can only attach an XLR connector to one end, as at the other end the cores will be in the wrong positions?

 

[SUNRAY]

It is a thing, some 2 core screened cable is made like this:View attachment 423666earth at the top hot & cold below, particularly FST cable (Foil Screened Twin) such as Belden 9501 etc.

Superimposed on an XLR can be a nice match with the hot and cold coinciding with the correct pins: View attachment 423667

Or on the wrong end they may need to be crossed over, here shown with hot and cold wires coinciding with the wrong pins: View attachment 423668

However when this popular method is used, and as an Ex BBC engineer that particular consultant insisted on it:

It really makes no difference.

 

[SUNRAY]

So does that mean if I take a length of such cable, I can only attach an XLR connector to one end, as at the other end the cores will be in the wrong positions?

No! It just means there will be a physical twist within the connector.

 

[morqthana]

I know, but all extension cables are prohibited

8.2.3.2 Marking of the plug for connection with the domestic installation
The following information shall be provided on the plug:
•
•
• A warning that plug-in solar devices shall not be connected to extension cable, multiway adaptor and RCD adaptor;

8.3.2 Information for assembly and commissioning
•
•
• Clearly state that the use of extension cables, multi-way adaptors, RCD adaptors and travel adaptors are not permitted;

So if someone ignores the warnings and clear statements, which Act or Statutory Instrument makes that an offence for which they can be prosecuted?

 

[SimonH2]

Do you mean a crossover in the sense of Pin 1 to Pin 2, and Pin 2 to Pin 1? When makers of XLR cables buy in a reel of cable, does the jacket have arrows on it so they know which way to use it?

No, it just means that instead of the cores lining up nicely with the pins, they have to be physically crossed to reach the right pins.

So does that mean if I take a length of such cable, I can only attach an XLR connector to one end, as at the other end the cores will be in the wrong positions?

One way round will be slightly easier, the other will also work, but needs a little more work. It's very marginal with a 3-pin XLR and a single screened pair, but with more pins, thicker cable, and so on, it can make a noticeable difference. Note that XLR connectors are very spacious compared to some others. In the past I've wired 8 pin mini DIN connectors (used to be used for Mac serial ports), there really is not a lot of space in those, so differences in how the cores align can make a difference.

No! It just means there will be a physical twist within the connector.View attachment 423673

That's it, but as above, with the generous space in an XLR connector, it's a trivial difference.

However, if you are terminating lots of cables, it does affect your rhythm if there are differences. You get into a flow if they are all the same, that breaks a little if they vary. I notice this with 4 pair network cables.

 

[SUNRAY]

One way round will be slightly easier, the other will also work, but needs a little more work. It's very marginal with a 3-pin XLR and a single screened pair, but with more pins, thicker cable, and so on, it can make a noticeable difference. Note that XLR connectors are very spacious compared to some others. In the past I've wired 8 pin mini DIN connectors (used to be used for Mac serial ports), there really is not a lot of space in those, so differences in how the cores align can make a difference.

I once had the task of terminating four 218 pin connectors, that's a plug and a socket each end of a pair of cables - specific connectors matched to the cables.
Unfortunately the cables had been run from one end rather than one from each end and no chance of turning one round. The connectors had to be cut and welded into a sleeve to extend it, something like this:

Originally it was around 200mm long and ended at arround 500mm.