Single 3-card HVI Backboard
with Power Supply Housing

The Teleline Isolator 3-card Shelf HVI Backboard Assembly, Model 751980/05 provides a safe, reliable, cost effective solution for isolating wireline communication circuits entering sites susceptible to high voltage influences due to Ground Potential Rise (GPR) caused by lightning and/or power faults.

The Teleline Isolator offers 70kV peak, 50kVrms protection on each communication circuit, while permitting continuous communications before, during, and after a GPR event.

Product Number CLEI Number Description Download Documents
751980/05   Single 3-card HVI Backboard
with Power Supply Housing
Installation Guide

3-card Shelf HVI Backboard Assembly


This HVI backboard assembly provides high voltage isolation for six (6) cable pairs entering a site and features the following:

  • IEEE 487 compliant
  • Teleline Isolator 3-card Shelf, Model 751127, certified to Safety Standard 60950, equipped to provide integrated Span Power for ADTRAN Total Reach®, HDSL and T1 terminating units
  • Entire assembly comes pre-wired to ensure dielectric separation of station and remote ground potential components, ensuring a safe and IEEE compliant installation
  • Equipment mounted on a ¾ inch (2 cm) thick plywood backboard with fire-proof paint:
    • Remote Ground Potential region designated in bright red
    • Station Ground Potential region designated in white
  • Station-side terminal block equipped with balanced, solid-state secondary protector modules
  • Connections to dedicated incoming communication cable (Remote Ground Potential) made via wire-wrap to ADC® high voltage isolation modules with looping jacks providing 20kV of isolation
    • Additional isolation jacks for circuit polarity reversal and shorting are provided for trouble-shooting purposes
  • Dedicated incoming cable protected by pre-installed 15kV lightning arrestor
  • HVI assembly provided with:

Note: * For integrated Span Power applications, use power supply 751318MC or 751319MC