Turner Stategic Technologies

Joint Base Lewis-McChord’s distribution system is a single-point-grounded system operating at 13,800 volts.  Joint Base Lewis-McChord has adopted Tacoma Public Utilities (TPU) design criteria as “industry standards” for utility construction.

Services Employed:

  • $1.2MM contract
  • Hundreds of Housing Units Serviced
  • 165- New Guy Poles
  • 244-Cross Arms
  • 65- Pole Mount Trans
  • 608- Insulators
  • 66,396′ FT- ACSR Bare Wire Primary
  • 37, 742′ FT- TRIPLEX Secondary w/full size ACSR messenger
  • 13, 100′ FT- Solid Wire

General Overhead construction requirements:

  • All new construction shall be underground unless dictated otherwise by special circumstance.
  • Pole-mounted three-phase transformer banks shall be no larger than 3-75KVA.  Pole- mounted single-phase transformers shall be no larger than 100KVA.
  • Pole-mounted transformers shall have separate ground for lightning arrestors, case grounds, and neutral conductor.  (Neutral ground is isolated per NESC.)
  • Construction shall be Grade B per the National Electrical Safety Code (NESC), ANSI C2.
  • Size, sag, and support overhead conductors per NESC and TPU standards.
  • Lightning arresters, appropriately sized, shall be provided at all risers, dead-end poles, and at each overhead and pad-mounted transformer. All cross-arms shall be 9 foot in
  • length unless application requires longer/larger arms.
  • Primary risers shall be constructed using alley-arm construction with arms parallel to main line
  • Splices and dead-ends shall be of the automatic type. Deadends shall be polymer-type.
  • Stirrups and other connections shall be made using compression type connectors listed for the application.
  • Fused disconnects shall be of the loadbreak type.
  • Power poles shall be rated Class 2.
  • Secondary conductor connections shall be made using compression-type connectors.


Turner Stategic Technologies- JBLM, WA | Electrical