Telephone extextension

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Hi, quick question - undoubtedly long answer!!

I have a customer who wants me to run telephone & fax lines to a porta cabin, the run is about 50m away from the master socket and will be ducted underground. The cable I was planning on using is product code "CA EXGPO5" from TLC.

I know that this cable is suitable for the conditions, but can I use a 5tp cable for 2 lines and would the cable length be ok??

 

Theorysparky

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Hi, quick question - undoubtedly long answer!!I have a customer who wants me to run telephone & fax lines to a porta cabin, the run is about 50m away from the master socket and will be ducted underground. The cable I was planning on using is product code "CA EXGPO5" from TLC.

I know that this cable is suitable for the conditions, but can I use a 5tp cable for 2 lines and would the cable length be ok??
Noz

Absolutely fine to use that cable, you only need the 4 pair max

as for the length thats not a problem but there may be issues from master socket to ext regarding the ring

i need to go away and look it up

 
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How about shifting the master socket to the porta cabin and ringing it back down the cable as a secondary??

You say 4 pair would do, I guess that is 2 pairs per line (which line, which contacts do I use??) - 5 pair seems to be the minimum they do in exterior grade!!

 
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You only need two cores to first point 2 and 5 and then 3 cores to any extension 2,3 and 5 although I always connect 4 cores 2,3,4 and 5. You have to be careful with tlc ext gpo cable as the second colours are white.

batty

 

Theorysparky

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You only need two cores to first point 2 and 5 and then 3 cores to any extension 2,3 and 5 although I always connect 4 cores 2,3,4 and 5. You have to be careful with tlc ext gpo cable as the second colours are white. batty
concur with that

if the master was going in the porta cabin ,,,, which is a better option

if you strip the outer cable you will find that they are paired if you untwist them carefully

 
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Hi, quick question - undoubtedly long answer!!I have a customer who wants me to run telephone & fax lines to a porta cabin, the run is about 50m away from the master socket and will be ducted underground. The cable I was planning on using is product code "CA EXGPO5" from TLC.

I know that this cable is suitable for the conditions, but can I use a 5tp cable for 2 lines and would the cable length be ok??
Are we talking TWO separate phone lines here...

1) a phone number used for bog standard Phone.

2) a phone number used just for fax machine?

Or...

Is it ONE telephone number with one of these combined .. phone/fax jobbies.. sharing the same line?

If two lines...

Then I would assume the FAX number will be dedicated to that fax machine..

with NO other extensions off it...

So the master socket for the fax would just be in the porta cabin..

with two wires (1 twisted pair) coming from the pole or the street or wherever..

up a pair of wires in your ducting to 'terminals 2 & 5' on the LJU socket.

The Phone line...

Some modern electronic phones don't need the third bell wire 'terminal 3'

so length may not be an issue anyway...

I don't think 50m is a problem..

you do need to consider how many other phones & extension sockets are simultaneously connected!?

hope that makes sense??? ?:|

if its come over as gobbledygook get Theory to prod me with that big stick he uses to keep the pigs in check!!! :D :eek: :O:p:p:^O

 
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What they are doing is moving an office from inside the house into a porta cabin. At present both telephone and fax lines terminate into two adjacent master sockets in the office.

What I was planning on doing was to run the porta cabin telephone & fax lines as extensions (they want to be able to answer the phone in the house during the evening) and also I'll be cheaper than BT!! This cable will go through a garage and down the wall into a duct which will go underground to the porta cabin and to 2 new secondary sockets...

Power is going to be taken via 40A MCB - 16mm 2 core armour - to the porta cabin isolator (TT'd at the porta cabin) house supply is TNC-S!!

 
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How about shifting the master socket to the porta cabin and ringing it back down the cable as a secondary??
Dont make a scrap of different to the length of the bell wire between terminal 3's...

Up OR Down the cable... tis still the same length?!!

It's more a question of where the rest of the secondary sockets are??

Nearer the existing incoming end or nearer the porta cabin...??

But as said 50m isn't that much of a length to worry about IMHO! ;)

 
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Cheers guy's, just thought that I read somewhere (obviously wrong)that there was a 20m max limit on customers side of master socket
Well that would exclude many a property I work at having any phone extensions!!! :^O :^O

In fact that rules out me own house as well!!! :eek: :O

I think that probably comes from them plug-in cheepo extn reel jobs with crap quality fine stranded conductors in them! :( :(

But using proper cable hard wired fixed correctly shouldn't be a problem..

Of course if you did have problems..

you could double up the wires..

i.e. Half the overall Resistance.. effectively reduce the resistive length of the normal single wire..

But don't think that would be needed anyway! ;)

 
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What they are doing is moving an office from inside the house into a porta cabin. At present both telephone and fax lines terminate into two adjacent master sockets in the office.What I was planning on doing was to run the porta cabin telephone & fax lines as extensions (they want to be able to answer the phone in the house during the evening) and also I'll be cheaper than BT!! This cable will go through a garage and down the wall into a duct which will go underground to the porta cabin and to 2 new secondary sockets...

Power is going to be taken via 40A MCB - 16mm 2 core armour - to the porta cabin isolator (TT'd at the porta cabin) house supply is TNC-S!!
So from what you say the Fax only needs to go to the new position...?

Not going to move the fax machine at night!?? :) ?:|

One other thought for consideration...

How many other existing extensions are there off the current socket position??? ?:|

Also it may be worth getting one of those plug in extension bell ringers...

from B&Q or the like!.. So when you have done your changes, you have an independent test bell that you can plug into the new socket and use it to check for ringing in.

 
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Yes, I guess that the fax will only be going to the new position!!

The fax has no extensions, and unfortunately I don't know about the phone

The ringer is a good idea, what I usually do is plug a phone in and ring it from my mobile..

Going to watch some TV now...

Night all:x

 
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Yes, I guess that the fax will only be going to the new position!!The fax has no extensions, and unfortunately I don't know about the phone

The ringer is a good idea, what I usually do is plug a phone in and ring it from my mobile..

Going to watch some TV now...

Night all:x
Yep good idea..

I also have a test phone... but as I said on one of my earlier posts..

many modern phones (with electronic ringy sounds) don't actually use the 3rd bell wire..

they just pick the ringing direct off the two A&B wires.

so you can still get ringing sound with 3rd wire open cct!

Whereas generally the physical BELL,, metal dome that rings!

generally does use 3rd wire..

so you prove all of your wiring to a more thorough level! ;) :D :)

 

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