200A Loabreak Elbow Connectors

Summary

The 200A loadbreak elbow is a separable connector suitable for connecting underground cable to padmount subsurface transformers and switchgear. Loadbreak and load make operations require the aid of a live-line tool (shotgun stick with elbow puller).

For application on ungrounded WYE or delta systems, the next higher voltage class product is recommended, for instance on a 15KV delta, the 25KV elbow should be used. Their ratings are always line-to-line, so a 15kV elbow will only be rated 8.6KV Line-to-Ground, so a 15kV delta will exceed the rating of the elbow.

The elbows kits are cable size sensitive due to the elbow lug needs to be crimped to the connector, and the elbow housing needs to provide a water tight seal around the cable insulation. [1] [2]

Application

Typically 200A Loadbreak Elbows are used to connect medium voltage cables to equipment. A load break elbow can be attached or detached live or under “load” and is typically rated for 200A.Elbows are used in the underground medium voltage electrical distribution industry to attach cables to equipment (such as a transformer or switchgear).Equipment will include:

  • Deadfront Padmount Switch Cubicle
  • Deadfront Padmount Transformers
  • Junction Cabinet

With a loadbreak elbow it can be used like an inexpensive switch, with a hotstick you can disconnect the load without disturbing the critical upstream portions of the distribution line. The loadbreak elbow also provides a visual open and can be "parked" on insulated parking bushings, or onto Feed-Thru's which then can be grounded with a grounding elbow.

Optional accessories allow system grounding, testing, bypass, surge protection and current limiting fusing. Additional connecting points and taps can be provided by use of junctions or feed-thrus.

200A Loadbreak elbows are typically not used in underground manholes simply because of tight spaces if linemen brush past the elbow with force there is potential to knock off a live cable because loadbreaks do no have bails to secure them on the equipment bushing, they are only secured with force fit and can be knocked off with force. This would cause a unsafe situation.

Installation

  • Concentric Neutral Preperation, Underground Primary Cable, 200A Loadbreak Elbow
    Elbow and Probe Recuperation, Probe, 200A Loadbreak

Components

Loadbreak elbows are sold in kits, and the kits are designed to fit specific sizes of cable. The essential pieces of the kits are:

  • Arc Quenching Probe
  • 200A Loadbreak Elbow Housing
  • Lug, Elbow, Compression, 200A
  • Probe installation tool
  • Silicone lubricant
  • Instruction sheet

The optional features within the components are:

  • Test point with cap on the 200A Loadbreak Elbow Housing
  • *Bi-Metallic (Copper top/Aluminum Compression Barrel) or All Copper Lugs

Note *:  that Bi-Metallic lugs can go on both Copper or Aluminum cable while copper lugs can only go on Copper cable. Bi-Metallic lugs make up the vast majority of lugs sold.

Industry Standards

All separable elbow connectors sold in North America need to meet the industry standards governed by:

  • IEEE 386-2006 – Standard for Separable Insulated Connector Systems for Power Distribution Systems Above 600 V

IEEE Standard 386 defines the specific interface dimensions that 200 Amp and 600 Series elbows, inserts, junctions, equipment bushings and any mating components must conform to ensure interchangeability.

Manufacturers

The major manufacturers of 200A Loadbreak elbows in North America are listed below by market share:

  • Elastimold (Brand, Owned by ABB)
  • Cooper Power Systems (Brand, Owned by Eaton)
  • Hubbell
  • Richards Manufacturing

15kV

Elastimold Cooper Hubbell Richards anufacturing
  
Available with a test point (capacitive), cable jacket sealing and/or shield grounding kit, compression copper lug, bi-metallic compression lug and CSA compression lugs Available with a test point (capacitive), cable jacket sealing and/or shield grounding kit, compression copper lug, bi-metallic compression lug, CSA compression lugs and 5kV Cable Adapter Available with a test point (capacitive), cable jacket sealing and/or shield grounding kit, compression copper lug, and bi-metallic compression lug Available with a test point (capacitive), cable jacket sealing and/or shield grounding kit, compression copper lug, and bi-metallic compression lug

25k/28kV

Elastimold Cooper Cooper PosiBreak Hubbell

35kV

Elastimold Cooper Hubbell

 

References

  1. Transmission & Distribution Material Stock Catalog, Chelan County PUD, 4/25/2012
  2. Underground Construction Standard, National Grid ST. 44.00.001, 2007