ABSTRACT: This Technical Reference (TR) provides the view of Telcordia on generic requirements for plug-in carbon block protector units used in central office connectors and building entrance terminals. The protector unit is a voltage or voltage and current limiting device that employs carbon blocks and heat coils or just carbon blocks. However, units meeting this criteria are not to be used to protect the 5ESS switching system.

This TR includes the functional design and operational criteria, the mechanical and electrical requirements, and the test methods for comparing the product against the stated requirements.