UNDERGROUND CONSTRUCTION
BOX, POLE TEST

Known as Box, Pole Test, these were used where a short trunk underground cable connected to overhead cable routes.  The liability to the cable due to lightning hitting the overhead wires is considerable and the Box, Pole Test provides for protection as well as a point for testing.  The box was fitted so it could be accessed at ground level.

There were various Box, Pole Test's with the G model being introduced circa 1909.

The Box, Pole Test F is a small wooden pole mounted box (13.5in x 7in x 7in), finished in grey paint.  This box was used to house Transformers, 7 Terminal or two Transformers No.4 or three Jacks No. 15 and 16.

The Box, Pole Test G is made of teak and painted a grey colour externally.  The doors are fixed with rubber seals and fixed by security screws.  They are produced in five sizes to accommodate 32 to 96 wires.

The compartment on the right hand side contains glass tube fuses (Fuse No. 202 or Fuse No. 2/2) , earthing bar, spark gap protectors and removable test plugs (Plugs No. 112), all fitted on 16 wire tablets.  The left hand side compartment provides incoming access for the underground and overhead cable feeds.

The wires are terminated on a tablet called a Protector, Fuse and Test No. 1601 which has provision for 16 wires.  This plate also has a metal cover and is earthed to ground.

Boxes, Pole Test were probably superseded by the introduction of the Protector, Unit Pole Top 15 Pair.

See Lines, Underground K3110 for further information

Drawings
Box, Pole Test F - CN481.
Box, Pole Test G - CN482.
Metal cover - 76729
Protector, Fuse and Test No. 1601 - 1905/0 and 1905/1.

Box, Pole Test D

Box, Pole Test E
This case uses Protectors C

Box, Pole Test G
This is a 48 wire cabinet and has 3 tablets (Protector, Fuse and Test No. 1601) of 16 wires each
The middle tablet has a metal cover fitted.
Right hand side door open.

Connecting the underground cable to a Box, Pole Test G

Working on a Box, Pole Test G