Series Multi-Stage Protection [SMP]
Let’s take a deeper dive into Furman 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 design of the circuit, it will not degrade over time (unlike most standard surge suppressors) and will show minimal increase in line impedance (unlike many advanced surge suppressors).
The SMP circuit is not simply designed to protect from a catastrophic surge, such as a near-hit 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 your equipment is exposed to on a daily basis. These common voltage fluctuations, 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 lockups, 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.
How SMP Works
Traditionally, surge suppression circuits have relied solely on components such as metal oxide varistors, silicone avalanche diodes, or active circuits with transistor devices (SCR’s). These robust components are designed to withstand the impact of an electrical surge or spike, and though they can do a credible job of clamping the rated voltage for which they have been designed, they have minimal immunity from large sustained electrical forces and can fail when tasked when presented with the challenge of a catastrophic surge.
Furman’s SMP circuit employs a hybrid design utilizing a non-sacrificial, multiple-stage inductance circuit of low-loss series inductors, DC rectifiers, and high voltage shunt capacitors to absorb the vast majority of energy in caused by a surge or spike, as well as a high-current MOV and thermal-fused varistor to reduce the remaining energy to a non-damaging level. With this topology, the SMP circuit is ensuring its own protection, while passing very little excess voltage to connected equipment – even when faced with a catastrophic surge. The circuit’s measured clamping voltage is 188 Vpk (this is equivalent to 133 Volts RMS, which is only 11% above an optimal 120VAC line) at 6000V/3000A input. For comparison, competing professional, non-sacrifical circuits have clamping voltages that we have measured in excess of 400 Vpk.
Furman SMP circuit measured with a 6,000V/3,000A pulse. Peak let through voltage = 188V.
Brand X non-sacrificial protection circuit measured with a 6,000V/3,000A pulse. Peak let through voltage = 461V.
SMP and EVS: Professional Protection for Professional Applications
Complementing SMP technology is EVS, or Extreme Voltage Shutdown. While SMP is ideal protection for transient spikes and surges, the circuit is susceptible to sustained overvoltage conditions, often caused by wiring faults within an electrical system (such as a disconnected neutral line). To protect against this occurrence, the SMP circuit includes Extreme Voltage Shutdown technology. This technology constantly monitors incoming voltage, and when voltage rises to an unsafe level for over a quarter of a second, it shuts off power to the SMP circuit and all connected equipment.
Since its introduction in 2001, Furman’s SMP and EVS protection technologies have proven themselves under the most demanding conditions for professional users around the world, whether on stage, in the studio, in the control room, at the front of house, in the backline, or in the theater. When downtime is not an option, professionals choose Furman
Furman Product Line
Merit Series
Most affordable rackmount power conditioners, power sequencer, voltage regulator from Furman
All models have Standard Level Surge Protection, Standard Level RFI/EMI Filtration, 9 Outlets, 15A, Protection OK Indicator, and Wall Ward Spacing
Model Options Available
Front Panel Retractable Lights
Digital Voltmeter
Power Sequencer
Voltage Regulator
Classic Series
All models utilize SMP Advanced Surge Protection, Linear Filtering Technology, EVS Voltage Protection
All models have 9 Outlets, Diagnostic Lights, Wall Wart Spacing, Isolated Outlet Banks, Front Panel Retractable Lights, and Rear Panel BNC Connector
Model Options Available
15A and 20A
LED Voltmeter models
Dual Voltmeter / Current Meter models
USB Charger models
Prestige Series
All models utilize SMP Advanced Surge Protection, Linear Filtering Technology, EVS Voltage Protection, Diagnostic Lights
15A and 20A
Digital Voltmeter
Dual Voltmeter / Current Meter
USB Charger
and more...
Model Options Available
True RMS Voltage Regulation Technology
Power Factor Technology
Clear Tone Technology
Global Voltage Regulation Technology
Symmetrically Balanced Power Technology
Contractor Series
Power Sequencers
All models utilize SMP Advanced Surge Protection, Linear Filtering Technology, EVS Voltage Protection
9 Outlets
20A Rating
Diagnostic Lights
Isolated Outlet Banks
Power Sequencing
Model Options Available
Mini Ports
Remote System Control Panels
Power Relay Accessory
Power Station
Power Conditioner Strips
6 or 8 outlets
15A Rating
Diagnostic Lights
Wall Wart Spacing
Broadband Data / Signal Line Protection
Model Options Available
SMP Advanced Surge Protection
Linear Filtering Technology
EVS Voltage Protection
Isolated Outlet Banks
Standard Level Surge Protection
Standard Level RFI/EMI Filtration
Pro Plugs
Professional Power Conditioner Strips
6 outlets
15A Rating
Diagnostic Lights
Standard Level Surge Protection
Standard Level RFI/EMI Filtration
Model Options Available
EVS Voltage Protection
Other Power Distribution Units
Battery Backup (UPS)
UPS solutions provide power backup in the event of a blackout and a full feature set designed specifically for A/V professionals
SMP Advanced Surge Protection
Linear Filtering Technology
EVS Voltage Protection
Battery Backup (Simulated Sine Wave)
Standard Voltage Regulation
8 Outlets
12A Rating
Diagnostic Lights
IR Blaster
Critical Load Outer Bank
Open Source Programmability
Power Control Software