Teleline Wireline Isolation


Multi-Card Shelf

For more than 30 years, the Teleline Isolator has been the number one choice for a communications facility High Voltage Interface (HVI) at electric supply locations. The Teleline Isolator isolates and protects telecommunications network facilities and personnel from the hazardous voltages associated with Ground Potential Rise (GPR) events caused by a power fault on the electric grid.

The Teleline Isolator unit breaks the continuity of the telecommunication provider’s incoming copper cable as it enters a substation while permitting bi-directional communications through dielectric materials. The Teleline Isolator separates the differing electrical ground potentials of the substation and ground potential of the broader telecommunications network, offers fail-safe protection within the systems' rated limits of 50kV rms, 70kV peak, and meets all the requirements of IEEE 487 for an On-Grid Isolator.

The Teleline Isolator product line accommodates virtually every type of communication circuit, is a modular system, and evolves with progressive innovations in high voltage protection.

Multi-Card Shelves

The shelves house the plug-in service isolation cards and system power supplies. The Teleline shelves meet UL94 requirements for flammability and UL60950 for electrical safety; they are available as three-card, five-card, or eight-card configurations.

Isolation Cards and Standalone Units

Many Teleline Isolator plug-in cards are also available as single-circuit, standalone high voltage isolation units. Each plug-in card or standalone isolation unit will protect up to 50kV rms, 70kV peak.


Supported circuit-types Include:

  • T1
  • DDS
  • OPX
  • ISDN
  • Dial-up modems
  • Protective relaying
  • POTS (Single, Dual)
  • 2W/4W AC Data
  • Adran DDS Total Reach
  • Ground Start and Loop Start PBX interfaces
  • xDSL (ADSL, all variants of VDSL, G-SHDSL, HDSL, HDSL2 and HDSL4)

High Voltage Interface Backboard or Fiberglass Cabinet Assemblies

Whether a backboard or cabinet assembly, all components of the HVI are positioned to maximize the effectiveness of the varied equipment based on experience and published IEEE standard 487.

For a small premium over a modular build-up approach, you will achieve a High Voltage Interface where all aspects of the protection equipment are situated for maximum performance. The Positron assemblies bring the benefit of uniformity to the HVI, removing the guesswork often resorted to when creating an HVI with a modular build-up.

Eliminating installation inconsistencies across a network of substations ensures the same high quality of high-voltage protection for telecommunications facilities and people.