IEEE C62.39

Description / Abstract: This standard sets terms, test methods, test circuits, measurement procedures and preferred result values for series connected, self-restoring current-limiter components used in low-voltage telecommunication circuit surge protection. It is only applicable for components in telecommunications circuits with sinusoidal ringing voltages up to 150 V rms at 15 Hz to 70 Hz and dc powering voltages up to 400 V. The selfrestoring current limiters covered by this standard have the following properties:

— Excessive current causes a transition from a low-resistance state to a high-resistance state

— Reverts to a low-resistance state when the excessive current ends

— Directly operated by the current flow through the component

— Solid-state (no moving parts)

— Withstands specified levels of impulse

— Withstands specified ac voltage levels when in the high-resistance state

Examples of this type of current-limiter technology are positive temperature coefficient (PTC) stepfunction thermistors of ceramic or polymeric material and silicon semiconductor based electronic circuits.

This standard does not cover self-restoring current-limiter components used in other applications, such as heaters, inrush-current limiters, or sensing devices. Current interrupting type components, which reduce the current to zero by a mechanical circuit break, are not covered by this standard. In this standard, a telecommunications circuit is a circuit that uses metallic conductors to handle the remote transmission of information, such as data, communications, and signalling.

Purpose

The test criteria and terms of this standard provide a means of component comparison and a common engineering language for users and manufacturers of self-restoring current-limiter components intended for use in low-voltage telecommunication circuit surge protection. The test and measurement of low-voltage telecommunication (data, communications, and signalling) surge protectors is given in IEEE Std C62.36™ [B6].¹ This standard provides the corresponding component tests for the surge protector non-surge and active tests.

¹ The numbers in brackets correspond to those of the bibliography in Annex A.