Hybrid protectors offer long life in harsh environments

These devices combine the best features of the breakthrough surge performance EdgMOV technology with an integrated Gas Discharge Tube (GDT) isolation structure. These protectors offer high reliability and long life in certain harsh environments.

The protector utilises a unique construction which fully integrates the classic GDT and MOV in a symbiotic relationship, (see figure), enhancing reliability and performance.

In this configuration, the GDT blocks leakage currents through the MOV that would otherwise lead to premature failure of the MOV device, while the MOV prevents the follow-on current (after a surge) that might damage the GDT.

Using proprietary computer-aided design techniques to model performance, Bourns engineers created the equivalent function of a discrete MOV and GDT in series.

After assembly of the core, leads are attached, and the unit is epoxy coated.

The result is a familiar radial disc MOV package that is only slightly thicker but has a substantially smaller diameter than similarly rated conventional devices.

The surge ratings of the protectors are typically comparable to the surge ratings of the next larger size of conventional MOV devices.

This offers designers the flexibility of choosing an IsoMOV protector that is a smaller diameter than the MOV option or choosing an IsoMOV protector of the same size as the MOV option and enhancing the surge capability of their protection scheme.

The IsoMOV Hybrid Protector Series offers an upgrade to nearly any MOV power application where premium performance and/or space savings are needed.

The extended temperature range, low leakage and superb energy handling density are especially advantageous to industrial and other applications exposed to high surges.

The device's graceful end-of-life failure mode quickly and cleanly blows the line fuse, never leaving equipment unprotected and eliminating the need for any indicator circuitry.

The IsoMOV protector family of products includes three unique series of devices: Model IsoM3, IsoM5 and IsoM8.

With nominal surge ratings of 3 kA, 5 kA and 8 kA, these revolutionary new protectors offer performance usually found in larger traditional MOV devices.

Bourns has produced a series of white papers around circuit protection utilising the IsoMOV Hybrid Protectors and other protection devices available from their portfolio.