June 2008

Focus on surge protection

Transient voltage, or a power surge, is an increase in voltage significantly above the designated level in a flow of electricity. Voltage is a measure of a difference in electric potential energy. Electric current travels from point to point because there is a greater electric potential energy on one end of the wire than there is on the other end. When the voltage increase lasts three nanoseconds (billionths of a second) or more, it is called a surge. When it only lasts for one or two nanoseconds, it is a spike. The main job of a surge protector system is to protect electronic devices from surges.

Surge protective devices

The VALVETRAB-SQ surge protective devices (SPD) offer safe, reliable surge protection from 40,000 to 200,000 amps.  The NEMA-style product series includes approximately 50 part numbers in three different mountable designs designated by CC (control cabinet), SP (sub-panel), and SE (service entrance) identifiers. 

The VAL-SQ CC series offers an economical method of protecting electronic equipment in light commercial, light industrial, and residential environments.  It has 40,000 amps of surge current rating, and its compact design is ideal for installation in a control cabinet or directly to critical equipment. 

With multi-phase SPD and noise filter, the VAL-SQ SP series protects sensitive equipment even in the worst environmental conditions.  It can be installed adjacent to sub-panels or directly to sensitive equipment.  It provides 80,000 or 120,000 amps of surge current rating per phase. 

The VAL-SQ SE series provides maximum surge protection for the service entrance and remote locations in industrial, medical and commercial applications.  Available with 120,000, 160,000 and 200,000 amp surge current ratings, it can be mounted near the circuit breaker, reducing connecting leads and improving performance.  In addition to surge protection, the VALVETRAB-SQ line includes status LEDs, audible alarms, sine wave tracking filtration and function monitoring. 

Phoenix Contact, www.phoenixcon.com


Compact surge protection

Specifically designed for small distribution panels, the ZoneDefender2 delivers cost effective, high capacity protection for a single phase application where size is critical. It provides AC and DC power surge protection with remarkable application flexibility thanks to its compact design.  Zonedefender2 provides protection between Line to Neutral, line to Ground, Line to Line, and Neutral to Ground. Using Metal Oxide Varistor (MOV) technology, the ZoneDefender's protection circuits are highly reliable, dual-redundant varistor networks that ensure your site is always protected. The ZoneDefender2 is fully automatic, immediately clamping voltage surges without causing undue leakage losses during normal operations.

The ZoneDefender2 offers the following features: AC or DC application; straightforward, simple installation; LED status indication via solid state diagnostics plus remote indication contacts; thermal and short circuit fusing; and UL 1449 Listed.

MTL Surge Technologies, www.mtlsurge.com


UPS power protection

The Smart-UPS RT 15kVA and 20kVA power protection models in a 12U size offer users a flexible electrical configuration of 1:1, 3:1, or 3:3 input/output wiring that avoids rewiring of the server room or network closet.

When implemented together, the Smart-UPS RT products can help IT and networking managers protect increasingly popular Power over Ethernet equipment investments against power overloads, outages, surges and spikes. The models, offering improved adaptability, availability, manageability and serviceability, are tested and certified for use within InfraStruXure architecture. They can support applications such as single high density racks using blade servers, as well as medical imaging and diagnostics, VoIP/IP telephony, industrial or factory floor machinery, RFID, and storage equipment. The Smart-UPS RT 15kVA and 20kVA are application optimized and compatible with a variety of operating systems and network management platforms.

The new models include hot-swappable battery and system fans, dual mains input, and an intelligent 3kW charger that automatically detects additional battery packs and adjusts charging voltage for faster recharge time. Notable highlights include: High density design in a 12U size that saves valuable space; configurable as single- or three-phase system offering flexible electrical configurations; and convertible form factor allows for rack or tower installations.

American Power Conversion, www.apc.com