BS 7671 Rules on Joining Cables.

[Lectrician]

Use a JB and be done with it. I would prefer that than a rubbishy heat-shrunk joint.

I'm curious, having noticed that most electricians believe a crimped connection to more reliable and longer lasting than a joint made in a screw terminal.

Lectrician - is your experience the opposite to that of most other electricians on the forum?

I have no problems with a crimped joint - ideal. It's the heat shrink I don't like. It has no BS number in terms of re-providing a sheath. Enclose the crimped joint in an adaptable gewiss-type box by all means.

I believe it is "frowned upon" to use compression type plumbing fittings beneath a floor - joints should be soldered, and preferably bends pulled by hand. Im no plumber though.......

 

[Softus]

No offence meant, but the analogy is flawed.

I assume, with electrical fittings, that safety is paramount, but with plumbing the the choice of plumbing fitting is a balance of compromises.

As well as all of the things I listed, cost is also a factor (both in price of materials and cost of deploying them).

 

[RF Lighting]

I assume, with electrical fittings, that safety is paramount

Is this not the same with gas, which is why compression fittings are not allowed if not readily accesible?

I may be well off the mark here, but this is my understanding of things.

A screwed joint may loosen over time through vibration and the like, but a crimped or soldered joint should be fine

A coleague of mine was called to a night club, after some of the lights had stopped working.
It turned out that the all of the screws in the switch have unscrewed them selves, cuased by the vibrations from all that bass.

.....Nothing a bit of loctite can't sort out

 

[Softus]

Is this not the same with gas, which is why compression fittings are not allowed if not readily accesible?

Ah yes, fair point, but I thought you were excluding gas because you referred to pushfit fittings.

A screwed joint may loosen over time through vibration and the like, but a crimped or soldered joint should be fine.

Phew! That was my simplistic understanding.

A coleague of mine was called to a night club, after some of the lights had stopped working. It turned out that the all of the screws in the switch have unscrewed them selves, cuased by the vibrations from all that bass.

Blimey.

 

[Pensdown]

No offence meant, but the analogy is flawed.

I assume, with electrical fittings, that safety is paramount, but with plumbing the the choice of plumbing fitting is a balance of compromises.

As well as all of the things I listed, cost is also a factor (both in price of materials and cost of deploying them).

Evening Softus, no offence taken.

I used that analogy because there are many ways of jointing cables just like there are many ways to jointing pipes all of which when done correctly achieve the same goal.

Crimps are very good when done correctly but if you read back a few posts you do need to use calibrated ratchet crimping tools to get it right because the tool head wears.

There is absolutely nothing wrong with a correctly terminated JB in a domestic environment but it's like everything else, you way up all of your options and select the one that best suits the application.

 

[RMS]

Agree with RF,

screw terminals are subjected to vibration due to the ac waveform fluctuating between +/- cycles.

Pensdown i think has summed this one up, all types of joints are permitted by the regs as long as the application is used and selected correctly.

526-03 and 526-04 has all relevant information.

 

[Softus]

Evening Softus, no offence taken.

I used that analogy because there are many ways of jointing cables just like there are many ways to jointing pipes all of which when done correctly achieve the same goal.

OK - I retract - the analogy works for me now that you've explained. Mebbee I didn't read back far enough in the topic.

...you do need to use calibrated ratchet crimping tools to get it right because the tool head wears.

It's a bloomin' minefield! I bought some rachet crimpers because I got fed up with trying to get stranded flex into immersion heater terminals, so I now crimp some pin terminals onto the flex. Unusual for a plumber perhaps, but I like things to be right. However, I had no idea that these can be or should be calibrated, but it makes perfect sense now that you mention it - a worn tool will crimp inadequately.

 

[RF Lighting]

I bought some rachet crimpers because I got fed up with trying to get stranded flex into immersion heater terminals, so I now crimp some pin terminals onto the flex. Unusual for a plumber perhaps, but I like things to be right.

Ha ha, good one.

You can't be a real plumber.

Next you'll be telling us you can lift and refit floorboards without destroying them.

 

[Pensdown]

I bought some rachet crimpers because I got fed up with trying to get stranded flex into immersion heater terminals, so I now crimp some pin terminals onto the flex. Unusual for a plumber perhaps, but I like things to be right.

Ha ha, good one.

You can't be a real plumber.

Next you'll be telling us you can lift and refit floorboards without destroying them.

Standard plumbers tool kit;

1. Kango for lifting floor boards
2. Chainsaw for notching joists
3. Nail gun with braided nails for replacing floor boards



And worst of all, an un-calibrated crimping tool

 

[Softus]

Next you'll be telling us you can lift and refit floorboards without destroying them.

I find a floorboard saw usually does the trick - preserve the tongue on one side and it slots back in quite nicely.

And worst of all, an un-calibrated crimping tool

Hm. I wonder which is worst - me unknowingly using an uncalibrated tool, or the supplier who sold it to me, or the manufacturer who packaged it up without a note explaining that it needs calibrating?

Or....the abundance of forum posts that mention crimping without mentioning calibration?

I believe the expression is ":lol:".

 

[Pensdown]

Sorry, I've spent most of my life communicating without keyboards and smiley things...(now which one should I pick) and the last two posts were suposed to be funny?

....oh. and by the way, that horrible bloke RF wrote "Next you'll be telling us you can lift and refit floorboards without destroying them"

 

[RF Lighting]

that horrible bloke RF

Horrible?

How rude

 

[Pensdown]

that horrible bloke RF

Horrible?

How rude

Did I miss another

LOL