STREET PILLARS


In 1945 the advice from a report on the provision of local cable distribution became BPO policy.  The cable distribution network would have main cables terminating in iron cabinets and then local cables radiated from these cabinets to either small pillars or direct to Distribution Points (DP's).

Pillars would in turn terminate the cable from the Cabinet and local cables would radiate to the Distribution Points.  These DP's were effectively the end of the external plant distribution and can be found on on poles, building walls and inside customers premises.

Pillars were already in use in Australia and the BPO adopted the same principle albeit with a slightly different termination design.

After the 1970's, Pillars were dropped and Cabinets were just used as the main distribution mechanism. 

The Cabinets and Pillars afforded flexibility in the network as any incoming wire could be connected to any outgoing wire.   The connection made by a piece of two wire called a "jumper wire".  In the early Pillars and Cabinets the terminals were actually screws which clamped the jumper wire or in the case of a through connection (i.e. incoming wire 10 to outgoing wire 10) then two metal pins were used (See picture to the right for the early model).

In the early 1970's the screw style terminal blocks were replaced with plastic formers and the cable wires just pushed through numbered holes and left hanging.  Connection between wires was made compressed crimps, called Connectors, Wire Insulated No. 1 (white coloured) or Connectors, Wire Insulated No. 1A (blue coloured and grease filled (See picture below).  These connectors were crimped with a tool called a Crimpers, Connector, Wire, Insulated No. 1 or  a Pliers, Crimping No. 2, which can be checked by a Gauges, Check 2.1mm.

Click here for more information on Crimps

The Pillar has five effective parts:-

  1. Base

  2. Terminal strip

  3. Moisture cover

  4. Outer cover

  5. Cover fixing bolt

The base had a 90 degree pipe leading from it through which the incoming and out going cables were fed.  The cables were  pre-terminated on the terminal blocks and jointed to the local cables a small distance away.

Due to being out in the open, the wiring and terminal block were then covered with a metal moisture sleeve which had a rubber gasket at the bottom.  Originally, desiccant was also left inside the Pillar, but this was later discontinued.

The outer cover was then put in place and a long bolt went through the base, which secured the cover.

The original outer covers were made of asbestos cement, but this material was rather fragile, so the covers were later made of steel.

Click here for more information on Pillars.

Pillar with later crimped connectors (Yorkshire Area)
The mounting is called a Strips Connection No. 1


Strips Connection No. 1 showing layout and numbering.
These replaced the screw type units and are also known as the Yorkshire type.


Later style steel cover
Note - The securing clamp is missing


In the above picture the terminal screws can be clearly seen.
In front of the Pillar is the cover securing clamp.

 

 
 
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Last revised: April 21, 2023

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