Storing conductor so it keeps its value

Two ways to stand a reel

A reel on its flange rim sits exactly as it was designed to sit: the two rims carry the load, the barrel holds the wind in shape, and the reel can be turned to spread the wrap or pay cable off cleanly. It takes floor space and it must be chocked so it cannot roll, and that is the whole cost.

A reel on end, resting on one flange face, saves floor space and is what most yards do. It is not free. The entire weight of the wind sits on the bottom flange and on the outer layer of cable, which flattens and takes a set. The flange can dish under the load. Water collects on the upper flange and runs into the barrel through the gap between staves. And the reel can no longer be turned, so the cable keeps the bend it acquired on the day it was set down.

The practical rule most plants settle on is this: store on the flange where there is room, store on end only when the reel is small, the stay is short, and the ground beneath is hard and drained. A reel that has stood on end for years will usually show a flat on the outer layer and slack wraps. Both are visible to a buyer from the first photograph.

Blocking, ground contact and weight

Timber bearers under the flange rims keep the reel off the ground, and they are not a formality. Wood wicks water, and a rim standing in red clay holds moisture against the flange for as long as the reel is there. The flange softens, the staves separate and the reel loses the rating it was built to.

Chock both sides, or put the reel in a rack. A 60 in. reel on a slight slope will roll once the surface is wet, and a rolling reel cannot be stopped by hand. On uneven ground, set bearers across the slope and chock against them.

Handling does damage that storage never does. Forklift tines go under the flanges, never against the barrel or the cable. Reels are rolled on their rims on a hard surface, never dragged on a flange face across gravel. A single bad lift can kink the outer layer and split a flange, and both are permanent.

Sealing the ends

Moisture enters stranded conductor at a cut end and travels along the strands by capillary action. It does not stop at the jacket and it does not dry out in a humid climate. On medium voltage cable the result is degraded insulation from the inside, which shows up later as a failed insulation resistance test and cannot be seen from the outside.

Factory end caps stay on for as long as the reel exists. When cable is cut, the end is re-sealed the same day: a heat-shrink cap, a mastic-filled cap, or a proper self-amalgamating tape wrap that covers the conductor and overlaps the jacket. One turn of PVC electrical tape is not a seal. It lifts at the edges, holds water underneath, and gives false confidence.

Paper-insulated lead-covered cable is the more demanding case. The seal has to keep the impregnant in as well as the moisture out, so a cut PILC end is sealed to the same standard as a termination stub. If an end has already taken water, do not seal over it. Report it, and let the reader decide.

Sun, heat and the jacket

Ultraviolet light attacks PVC, polyethylene and rubber jackets. Black jackets resist it because of the carbon black in the compound; coloured and thin jackets chalk, craze and crack, and a cracked jacket is an entry point for water that no test will find until the cable is in service.

Heat is the second half of the problem. A reel standing in full Georgia sun in July is hot enough that the jacket softens under its own contact pressure, and the outer wraps can shift or bond to each other. Thermal cycling between day and night works the wind loose, so the outer end slackens and the cable drops.

Shade is the cheapest fix, followed by an opaque cover. Clear plastic sheeting is worse than nothing: it traps condensation against the jacket and magnifies nothing useful. Keep the tag facing out and legible, and never paint or stencil over it. A legible tag is the only document most surplus cable has.

Stacking, rodents and the damage that cannot be undone

Reels are not pallets. Stacking is only acceptable where the reel was built for it and the load sits on the flanges, never on the cable. A reel standing on the wind of the reel below crushes the outer layer and distorts the wind of both. Wood reels in a Georgia yard also attract termites and rodents, and a chewed outer layer is a full loss of the outer layer.

• Water in the strands. It cannot be dried out of a long length, and it is not visible in a photograph of the flange.
• A sun-cracked jacket. The damage is in the compound, not the surface, and no wrap restores it.
• A flattened outer layer from years on end. The cable will not straighten.
• A cut end left open through a rainy season. The wet length is scrap.
• Flange rot and split staves. The reel stops being liftable, so the cable cannot be moved without rewinding it.
• A collapsed wind, where inner layers drop and the outer wraps slacken. Recovering it means rewinding, which is a factory job.