FP Cable Is Not Always Suitable

[Guest111]

The last lad I trained asked about pyro at college and was told they didn't do it any more as it was a bit of a black art eventually I can see it being a specialised thing if something isn't done to improve training at college,lets be honest it's still widely used in certain areas so should still be taught as part of normal trade training.

 

[davesparks]

I was taught the same way mate as many others will as its good practice. I had a conversation with a guy from Cormeton once who was commissioning a fire alarm system that had been extended from pyro to fp and he said ut can cause problems. Cant remember the reason he gave I think it was on an adressable system so may have been something to do with the systems knows which way accessories or set at or something along those lines. (Im not mega clued up on the technical side of fire alarms)

That sounds like a bit of old bull to get around him being unable or too lazy to do it properly.
It's easy enough to get the polarity right on a bit of pyro, and I'm sure a earthed solid copper sheath is better than a bit of tin foil wrapped around the cores as far as screening goes.

 

[DRG]

You're probably right mate

 

[shanky887614]

first attempt at 2l1.5 using double pliers method

lovely stuff to work with, I don't know why some people really don't like it

 

[davesparks]

How did you get the seal crimped into the pot without stripping a bit more sheath back to get the crimped round it?
It may be an optical illusion but it doesn't look like you've stripped enough sheath back to me

 

[shanky887614]

How did you get the seal crimped into the pot without stripping a bit more sheath back to get the crimped round it?
It may be an optical illusion but it doesn't look like you've stripped enough sheath back to me

yup your right, I havent actually threaded it as far as I should have.

its caught a little bit of thread but I didnt realise how far it was supposed to go till I just did more research on youtube.

 

[Guest77]

yup your right, I havent actually threaded it as far as I should have.

its caught a little bit of thread but I didnt realise how far it was supposed to go till I just did more research on youtube.

What dave means is you need to strip back more orange sheath so you can slide the gland back, you need to crimp the cap into the pot firmly, you can't do that with the gland in the way fella.

 

[shanky887614]

What dave means is you need to strip back more orange sheath so you can slide the gland back, you need to crimp the cap into the pot firmly, you can't do that with the gland in the way fella.

true, to be honest Its a bodge at home till I get hold of a crimper.

I crimped it into the pot by putting one side of the grips on the very bottom on the gland and the other side on the top of the pot.

I would like to have used a proper crimper but I don't have access to one at the moment

 

[Guest77]

true, to be honest Its a bodge at home till I get hold of a crimper.

I crimped it into the pot by putting one side of the grips on the very bottom on the gland and the other side on the top of the pot.

I would like to have used a proper crimper but I don't have access to one at the moment

aye I know pal, bear with me.

 

[davesparks]

Yeah sorry, I meant the orange over sheath not the copper sheath, I should have made myself clear.

 

[trev]

first attempt at 2l1.5 using double pliers method

lovely stuff to work with, I don't know why some people really don't like it

It's not so much that they don't like it, more that they're scared of it. I agree, I think it's fantastic stuff.

 

[shanky887614]

Yeah sorry, I meant the orange over sheath not the copper sheath, I should have made myself clear.

I used a pair of tiny grips I have to screw the pot on but I didnt screw it in fully.

that answer your question?

 

[trev]

Not bad for a first attempt, I've seen a lot worse. Did you IR it?

 

[Guest77]

when you screw the pot on you only want the bare cable sheath to just be level with the top of the threads inside the pot, I always pull the cores with a pair of pliers before adding compound and blow out the powder so the pot is clean and dust free. When you get a crimper which hopefully will be early next week you need to ensure the gland slides back away from the pot so you can really get arount the whole pot to crimp it up tight, apart from a couple of basic mistakes your attempt looks good, it is straight and the cores look in good condition, practice makes perfect :rockon:

 

[shanky887614]

when you screw the pot on you only want the bare cable sheath to just be level with the top of the threads inside the pot, I always pull the cores with a pair of pliers before adding compound and blow out the powder so the pot is clean and dust free. When you get a crimper which hopefully will be early next week you need to ensure the gland slides back away from the pot so you can really get arount the whole pot to crimp it up tight, apart from a couple of basic mistakes your attempt looks good, it is straight and the cores look in good condition, practice makes perfect :rockon:

attempt 2 so far

ill leave the compound off till I get a potting tool.

im going to take into work in the morning then ill ir it. (im at home and dont have an ir tester)

 

[davesparks]

Looks good from here, cable sheath just half a gnats whisker inside the pot and the earth tail in the right position relative to the cores.

Grab the end of the cores with a pair of pliers and give them a good hard tug to straighten then out, it'll make sliding the seal on a tad easier.

 

[shanky887614]

Looks good from here, cable sheath just half a gnats whisker inside the pot and the earth tail in the right position relative to the cores.

Grab the end of the cores with a pair of pliers and give them a good hard tug to straighten then out, it'll make sliding the seal on a tad easier.

didnt realise it was so ****ed

afterall ****ed is the new straight, feel free to call me neville XD

 

[Guest77]

Agree with dave, a good tug with pliers on the 2 cores and it is looking good

 

[djw]

Not bad for a first attempt, I've seen a lot worse. Did you IR it?

You probably saw one of my first attempts Trev!! Got a right ear-bashing for it... no shroud, pot not straight and screwed on to far...

btw - I've a spare one of these if MDJ can't set you up...

Edit - didn't realize the pic was that big, i'ts only for 20mm pots

 

[trev]

As an apprentice I was given scrap ends to make off, After a while and some intense inspections of my efforts I was allowed to use potting compound. The first end I made off that actually went into service made me a very proud puppy spark.
Afaik it's still there to this day.

 

[shanky887614]

As an apprentice I was given scrap ends to make off, After a while and some intense inspections of my efforts I was allowed to use potting compound. The first end I made off that actually went into service made me a very proud puppy spark.
Afaik it's still there to this day.

your gran kids might get the chance to rip it out while complaining its better than what they are replacing it with you never know

 

[trev]

Well so far we're one from three and it looks like it's staying that way. Grandson will not be a spark if I've got anything to do with it.

 

[tazz]

No point in testing until you have potted the gland......this will be another learning curve, testing the insulation with one reading..then testing 24 hours later, with another reading. Full marks, for taking the time to practice and post your results. In the next few years, when industrial projects need installing and renewing...The quick course guys will be left to their house bashing, whilst others will be back in the thick of it.

 

[Dcf]

A decent effort.
when doing it for real remember and put the compound in from one side only of the pot.
keep the compound clean and free from bits of swarf etc.
i wouldn't blow in the pot as mdj suggests I would give it a tap and make sure it's clean myself
like all black arts practice is the key

 

[trev]

Blowing in the pot is potentially bad news. You could have bits of swarf in there which could blow up into your eyes.
Tappy tappy is much better.

 

[shanky887614]

Blowing in the pot is potentially bad news. You could have bits of swarf in there which could blow up into your eyes.
Tappy tappy is much better.

to be honest I didnt blow into it, I wiped conductors first to get rid of most of it then tap.

I didnt touch compound either, I used the wrapper and overfilled it from one side to stop the formation of any air pockets

 

[davesparks]

Beware of a tiny thread of brass/copper swarf which can sometimes appear in the pot as you screw it onto the cable.

Also pop the megger on it before you put the compound in, and then just before you crimp it, and then after you crimp it. this was you have a chance to correct things before you crimp it and get to the point of no return.

 

[stevethesparks]

The reason I was taught not to blow in a pot is because the moisture from your breath can dampen the mineral - of which would be sealed in with the compound.

 

[tazz]

Shanky...are you using a cutting compound or oil when cutting....if you find this messy, old trick from an old sod...is use a candle, just as good, less mess and saves you joist blade

 

[trev]

The reason I was taught not to blow in a pot is because the moisture from your breath can dampen the mineral - of which would be sealed in with the compound.

While it's a possibility the likelyhood of it happening is fairly low