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Phone Line Identification
Identifying a phone line
The humble phone line has had many different changes since its inception into Australia.
We have tried to list the most common ones to help people identify them if found during renovating.
When in doubt, treat every phone line as alive. This may avoid costly repairs.
If required, Phoneworks can send out an experienced telecommunication technician to identify and/or repair the cable!
External Phone Line cables
1. Armoured Cable
An underground lead phone line has to have additional protection from damage, so the idea to wrap the phone line/s with layers of wire had developed.
This type of cable was referred to as "Armoured Cable"
2. Polyethylene Sheath cables
These black plastic sheath cables were made with UV inhibitors and are the only phone line cables that should be used outside a building. The UV inhibitors prevent the cable from deteriorating and eventually causing faults. These cables are used to feed a building from the street network or exchange.
Modern Polyethylene sheath cables were filled with a type of jelly or grease to slow down the ingress of moisture in the event that the sheath was damaged.
3. Hard Jacket cables
Some external phone line cables are made with an additional external PVC layer to protect them from being damaged by ants and termites.
This cable is designed to be dropped into an open trench without a conduit.
Hard jacket cables are cheaper to install over long distances than pipe and are therefore better suited to rural installations.
Note! Phoneworks doesn’t recommend this type of installation on properties where the installation distances are less than 300 meters due to the costs and problems associated with repairs if the phone line is ever damaged.
Internal Phone Line cables
1. Lead Cable
This phone line consisted of two copper wires which were insulated by cotton or paper.
The pair of wires was protected from moisture by a lead metal sheath, grey in colour and referred to as "lead cable".
2. 2 Pair Tech Wire (cat 3)
Commonly used with phone line installations.
This cable consists of 4 wires, blue, white, black and red with a cream coloured outer sheath and is capable of carrying up to two separate phone lines.
3. 3 Pair Tech Wire (cat 3)
This cable is consists of 6 solid core wires, blue, white, black, red, green and gold with a cream coloured outer sheath and is capable of carrying up to three separate phone lines.
4. Cat 5 or cat 5e
Cat 5 cables can be used as a 4 phone line cable or as an Ethernet / Data cable.
This cable has eight solid core copper wires and is ideal for new house pre-wire installations as it has the capacity to carry up to 4 different phone line services.
The different twist rate on each pair of wires prevents induction from services onto the other 3 phone lines. Outer sheath cables are generally blue or grey in colour.
There are 4 pairs of twisted wires. The first pair of wires is blue with a blue white mate, the second pair is orange with an orange white mate, the third is green with a green white mate and the forth line is brown with a brown white mate.