January 26, 2022

The National Electrical Manufacturers Association (NEMA) published NEMA C29.14b-2021 Composite Insulators Guy Insulator Type (Uncoated or Painted Type).

This new standard covers composite guy (strain) type insulators for utility poles that are made of a fiberglass-reinforced resin matrix core rod and metal end fittings. These insulators are used on overhead distribution lines for electric power systems to insulate or isolate guy wires for corrosion protection, increased insulation levels, or clearance for maintenance and normal operation. The guy wire connects the ground anchor to the top of the pole.

“This new standard is beneficial for industry users because it defines the mechanical and electrical performance requirements that ensure proper fitment and coordination of the guy strain insulator in the guying system (bracing system),” said Mark R. Burns, Preformed Line Products, and vice chair of the NEMA High Voltage Insulator Committee. “This eliminates guess work for utility design engineers when matching the appropriate fiberglass guy strain insulator with their systems.”

“The C29.14b specification brings the confidence of performance to an insulator that has been used in the industry for decades,” he said.   

This standard is written for electric utilities companies.

NEMA C29.14b-2021 is available on the NEMA website for $53 in hard copy and at no cost as an electronic download.