Series Multi-Stage Protection

With SMP, there is virtually no downtime. In fact, the circuit is tested to handle multiple 6000 volt or 3000 amp pulses without sustaining any damage. This is far beyond the demands placed on typical surge suppressors. But because of the extreme conditions and critical applications faced by Furman’s clients, the SMP circuit has been designed to pass this severe test and ensure that equipment damage or maintenance is extremely unlikely.

Furman’s SMP relies on a network of components to slow down the impact of a potentially catastrophic surge by capturing it, dissipating it in the form of heat, and absorbing the remaining excess energy. When tested with multiple 6,000V/3,000A surges, the SMP circuit’s maximum let-through voltage is 188V Pk (133V RMS – only 11% higher than a nominal 120V line). Due to the circuit design, it will not degrade over time (unlike most standard surge suppressors) and will show minimal increase in line impedance (unlike many advanced surge suppressors).

Furman SMP Circuit

188V Pk measured let-through voltage

Typical Non-Sacrificial Circuit

T461V Pk measured let-through voltage

Engineered for Maximum Life

The SMP circuit is not simply designed to protect from a catastrophic surge, such as a lightning strike, it is engineered to provide maximum life to connected equipment. This means it not only protects from devastating spikes and surges, but also offers protection from the dozens to hundreds of small spikes and surges that your equipment is exposed to on a daily basis. These common voltage surges, although small, can have a serious adverse effect over the long-term. Even when protected by a standard surge protector, digital circuits can see long-term damage due to exposure to voltage on the ground line, causing intermittent behavior, equipment lock-ups, and data loss.

By absorbing these everyday surges without deterioration of the circuit or contamination of the ground line, Furman’s SMP maximizes the longevity of connected equipment and minimizes the risk of downtime or failure in mission-critical applications.

Mission Critical


We deployed the Furman power protection and management products in the Sky Suites and at the FOH mix position, all critical locations.”

— Pete Dugas| TSAV