Transformer connections · Georgia
We buy transformer lead cable and connections
The short, flexible, heavily stranded copper that ties a transformer to its switchgear. It is cut to fit one installation, terminated at both ends, and reviewed by piece and by lug rather than by the foot.
- Rope-lay copper
- Compression lugs
- Cut to fit
01Overview
What this page covers
A transformer does not connect to anything with a straight run of cable. The connection has to absorb vibration, allow for thermal expansion and fit inside a cable box or a throat, so it is made from flexible rope-lay copper, cut to length and terminated with compression lugs. On the low side the same job is often done with copper bar.
When a transformer is replaced, the leads and the bar are cut out with it. They arrive as short pieces with lugs on them, and in older stations as paper-insulated lead-covered leads running to a manhole. Because they were made for one unit, they are a set rather than a stock item, and none of it is bought by footage.
02Specification
What a transformer connection lot contains
- Voltage
- 600 V on the low side; 15 kV and 25 kV on the high side
- Conductor
- Flexible rope-lay copper, 4/0 through 750 kcmil
- Terminations
- Compression lugs, two-hole NEMA pads, flag lugs
- Low-side bus
- Copper or aluminum bar, 1/4 in. by 2 in. to 1/2 in. by 6 in.
- Assemblies
- Pre-cut leads, neutral cable, ground braid, bus links
- Condition
- New spare, cut from a retired unit, oil-soaked, lug corroded
- Documentation
- Transformer nameplate, connection drawing, cable schedule
- Reels
- Coils and short lengths; a full reel is unusual
Photograph each lead with a rule against it and count the lugs. The copper is weighed, but the assemblies are what a buyer can actually use.
03What we buy
What we buy
Flexible rope-lay leads
High strand-count copper, built to bend without fatigue in a vibrating connection. Reviewed on strand condition at the lug and on whether the lug was crimped or soldered, because a soldered lug on a lead is a repair that has to be cut off.
Low-side bus and throat connections
Copper or aluminum bar between the transformer throat and the switchgear, with drilled pads and flexible links. Reviewed on thickness, hole pattern and whether the plating survived the removal.
Paper-insulated transformer leads
Older stations used lead-covered paper leads from the transformer to a pothead or a manhole. Short, stiff and lead-sheathed, and reviewed like any PILC material once the sheath is checked for cracks.
Neutral, ground braid and jumpers
Neutral conductors, braided ground straps and short jumpers between bushings. Small items that are easy to lose and worth counting, since a braid that has lost its flexibility is copper and nothing more.
04Evaluation
How a connection lot is reviewed
Count the pieces and the terminations. A transformer connection lot is a set of assemblies, and each one is described by conductor size, length, lug type and condition. That description is what makes the lot useful to another utility or contractor; a weight ticket makes it scrap.
Then the copper. Flexible lead is high strand-count, which means a lot of surface area to corrode, and a lead that sat in a cable box with water in it will show green verdigris through the strands. That does not remove the copper value, but it does remove the assembly value.
Then the bar and the hardware. Plated bar that has been drilled, filed or bent is reviewed on weight. Bar with its plating and its hole pattern intact is a spare part, and a spare part is worth more than the metal in it.
A transformer is not dead because its breaker is open. Windings hold residual charge, a transformer can be backfed from the low side, and the bushings and cable box are the places where that becomes a shock. Nothing inside a cable box is opened until the transformer has been isolated, grounded and, where the leads are to be cut, drained of oil by the owner.
05Seller terms
Before you sell: how it works
Four things a seller should be able to pin down before a truck is booked.
Verification
Footage is checked against the reel tag, the sequential marks on the jacket, the wrap count against the barrel, or a published weight per 1,000 ft — whichever the reel actually supports.
Payment
Payment method and timing are agreed in writing for the specific lot before anything is loaded or moved. No verbal number is treated as an agreement.
Paperwork
A bill of sale for the lot, and for utility material the owning utility’s release reference. Neither is optional and neither is created after the fact.
Freight
Collection is arranged as part of the terms. Say what can lift the reels and whether a 53-foot trailer can reach them, and the pickup is planned around that.
Sending a reel list and photographs costs nothing. A review is not a purchase, and nothing is bought, moved or scheduled until written lot terms are agreed for that material. Request a pickup when the lot is ready.
06Related
Related material
07Questions
Transformer lead cable questions
Are transformer leads bought by length or by piece?
By piece. They are cut to fit one installation, so each lead is described by conductor size, length, lug type and condition, and the copper is weighed alongside that.
Do you buy the flexible braid and neutral cable?
Yes, as part of the connection lot. Braid is counted rather than weighed, and a braid that has stiffened or cracked is reviewed as copper.
What about lead-covered transformer leads in an old station?
They are reviewed as paper and lead cable. The sheath is checked for cracks and the lead is recovered with the copper, under the same handling precautions as any lead cable.
Does a transformer nameplate help?
It identifies the unit and its ratings, which sets the size of the leads and the bar. The connection drawing is more useful for quantity.
Send the lead count and a photograph of a lug
Conductor size, length, lug type and the number of pieces describe a connection lot. The nameplate and the connection drawing confirm it.