2017 National Electrical Code®: Changes in Overcurrent & Surge Protection

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2017 National Electrical Code®: Changes in Overcurrent & Surge Protection

Mersen recently released a guide to understanding its changes in overcurrent and surge protection in the 2017 National Electrical Code®. These changes are to increase worker safety and help prevent arc flashes.

Arc flashes are the result of a massive release of energy due to an arcing fault between two phase bus bars, neutral or a ground.  This energy discharge burns the bus bars, vaporizing the copper and thus causing an explosion, which destroys everything in its vicinity and creates deadly shrapnel as it dissipates. Short-circuit current ratings (SCCR) indicate what fault current a system can handle without unacceptable damage in the case of a fault. Proper documentation is essential to ensure the available short-circuit current does not exceed the SCCR and that suitable precautions are in place.

We offer Mersen safety solutions to help you comply with the updated code and increase your workplace safety. Mersen’s guide covers nine key changes to the 2017 National Electrical Code®:

  1. Arc energy reduction

    Any fuses rated 1200 A or higher must have their location documented and available. The fuses must also have a method to reduce clearing time if their clearing time is not already 0.07 seconds or less.

  1. Field marking of available fault current

    Industrial control panels, industrial machinery and motor controllers of multimotor and combination-load equipment must have the date the current short-circuit calculation was performed and available short-circuit current rating (SCCR) documented.  If the available short-circuit current exceeds its short-circuit current rating, they shall not be installed. Elevators must also have the maximum short-circuit current clearly marked.

  1. Branch circuit and ground fault protection for single motor power conversion equipment

    Semiconductor fuses and instantaneous trip circuit breakers must now be installed as a single unit if instantaneous trip circuit breakers are permitted.

  1. Short-circuit current rating for elevator control panels

    Elevator control panels must be marked with their SCCR. If the available short circuit current exceeds its short-circuit rating, elevator control panels shall not be installed.

  1. Surge protection for emergency elevator, dumbwaiter, escalator, moving walk, platform lift, or stairway chairlift

    Surge protection shall be provided if the elevator has been designated as supplying an emergency system load.

  1. Surge protection for critical operations data systems

    A cascading protection scheme should be used throughout the entire operations data system.

  1. Surge protection for industrial machinery

    Industrial machinery with safety interlocks are required to have surge protection.

  1. Surge protection for fire pump controllers

    Surge protection was required previously for emergency systems at distribution level, but are now also required in or on the fire pump controller.

  1. Short-circuit current rating documentation and field marking

    Transfer switches can often have several different SCCR, so the rating based on the protective device and settings shall be externally marked.

Want to learn more about the changes in the 2017 National Electrical Code® or how best to implement them in your workplace? Contact your French Gerleman Account Manager or e-mail info@frenchgerleman.com to learn about Mersen safety solutions.


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Staying Ahead of the Electrical Trends and Standards

Last month, at our St. Louis branch, we offered customers the chance to learn about the latest trends and standards within the electrical industry at our Trends and Standards Update. Attendees gained knowledge on the latest innovative products that can help customers stay compliant with standards and the latest trends to help drive safety, technology and efficiency.

These high-level presentations offered cutting edge solutions to help customers stay ahead of the electrical trends and standards.  The seminar offered updates from Mersen, SolaHD, Thomas & Betts, Hubbell Wiring Device- Kellems and LUTZE.

These presentations covered the following:

Mersen covered SCCR codes and standards, including UL 508A standards. The UL 508A marking confirms that the industrial control panel has been certified by inspection. If the UL 508A’s construction requirements are followed, then a panel builder is eligible to have their panel listed by UL. Mersen also explained short circuit current rating (SSCR) and the importance of properly labeling panels for Arc Flash compliance.

SolaHD has updated its SDU Series DIN rail AC UPS. Their A Series still combines an industry leading compact design with a wide operation temperature range and unique installation options. The SDU provides protection from impulses and power interruptions that could be potentially damaging. This updated product also offers a new interchangeable optional “COMM Card” accessory, that allows communication between fieldbus protocols and industrial Ethernet. SolaHD has also introduced a new CF Relay Card option that has replaced the RELAYCARDSDU option.

Thomas & Betts has created an evolution of compression tools. Their Color-Keyed coding system allows high quality UL-compliant connections at a low installed cost. Thomas & Betts covered the basics on how to properly prepare cable, determine the proper connector, choose the correct tool/die and crimp inspection. They covered how the Thomas & Betts Blackburn Color-Keyed® compression connector system can make inspections and certified installations easier.

Hubbell Wiring Device-Kellems recently released the first UL Listed pop-up receptacle for countertops. To protect against spills, the receptacle assembly is sealed with patent pending silicone gaskets to repel liquids in both the down and up positions. The countertop receptacle is UL Listed to 498 Section 146 to be water resistant to a half gallon of liquid spilled on the device.

Hubbell also recently introduced both their Advantage Pin & Sleeve product line to promote safety and provide line of site disconnect and their inSIGHT Circuit-Lock™ Disconnects with LED indicators to promote workplace safety and improve troubleshooting time.

LUTZE covered the evolving NFPA 79 standard. The recent changes to this standard aligns with IEC 60204-1. A change to Section 6.6 states that an arc flash hazard warning requires “warning qualified individuals of a potential arc flash hazard” pertaining to emergency stop or emergency off situations. New work space rules for enclosures with feeder conductors have been revised to align with section 110.26 of the NEC. To help users avoid dangerous errors the requirement for “width of working space” has been revised to specify the required opening and clearance into the control cabinet. LUTZE has a variety of cable offerings that meet the NFPA 79 standard.

Be sure to check out our website for information on upcoming events.  If you have questions or would like more information on products or concepts covered in this recent event, please contact your French Gerleman account manager or e-mail info@frenchgerleman.com.

 


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Product Spotlight: Mersen Surge Protection

Did you know that power related fluctuations cost US companies more than $80 billion a year? Down machines cost you money, time and resources. Instead of spending thousands of dollars to fix or repair your expensive machinery, for a minimal investment, you can protect your sensitive equipment, or your entire facility, from electrical surges.

Most surge spikes occur from within a customer’s own facility. Nearly 80% of all surge problems are directly attributed to power disturbances from a facility’s own equipment. So who is at risk for a surge spike? If you have a facility with motors that are stopping and starting, load panels being turned on and off on a regular basis and other potential power disturbances, then you are at risk for damage.

What types of damage can a surge cause to a facility? Can it really be that bad? The short answer is YES and can be described by the 3-Ds.

  • Disruptive: A surge enters an electronic component, which then in turn, interprets the valid logic command. The result is a system lock-up, machine malfunction, leading to faulty output or corrupted files.
  • Dissipative: This is a repetitive pulsing of short duration energy, which results in long-term machine or system degradation, leading to system replacement sooner.
  • Destructive: This is caused by a high-level energy surge that immediately results in equipment failure, or complete destruction.

Protecting your equipment, and facility, is more important now than ever. At French Gerleman, we carry the Mersen Series SPD units: STXH, STXR, STXP and STXT. Here’s a description of each and how they can help you.

STXH Series:

The Surge-Trap Type 1 STXH is the most compact of the STX series, and meets all requirements for UL1449 Fourth Edition. It is suitable for any 120/240VAC split phase application, and features TPMOV® technology inside, meaning it is the safest product available in its category. Due to the small size, the performance and reliability, the STXH is ideal for HVAC applications and direct mounting to air condition disconnect switches.

Product features and benefits:

  • Designed with the industry leading Mersen TPMOV® technology
  • Compact footprint designed to mate with AC Disconnect Switches
  • LED status indicator
  • NEMA 4X enclosure for indoor and outdoor use
  • Fits 1/2″ knockouts with 18″ leads
  • For use in ANSI/UL Type 1 or 2 SPD installations
  • Features 3 modes of protection (L-N, L-L)
  • 3-year warranty

STXP Series:

The STXP Series offers advanced performance and features over the STXR series, including higher surge capacity and phase LED status indicators. It meets the UL1449 Fourth Edition Requirements and was designed for additional mounting flexibility, including mounting feet and flush-mount capability. Like the others in this line, the STXP features TPMOV® technology inside, making it the safest product available. This product is the perfect fit from service entrance all the way down to an important machine specific control panel.

Product features and benefits:

  • Designed with the industry leading Mersen TPMOV® technology
  • Features enhanced 100kA surge capacity for longer life and higher single impulse withstand
  • Pre-wired with 3′ leads for easy installation
  • Up to 10 modes of protection (L-N, L-L, L-G, N-G)
  • Features a 10-year warranty

STXR Series:

The STXR is the most popular model in the STX range, meeting requirements for UL1449 Fourth Edition. It is ideal for the replacement of obsolete surge arrestors. With a small, compact design and line or load installation flexibility, the STXR series is the perfect fit for branch panels or individual equipment protection.

Product features and benefits:

  • Designed with the industry leading Mersen TPMOV® technology
  • LED status indicator (ON=good, OFF=replace)
  • NEMA 4X enclosure for indoor or outdoor use
  • Fits 3/4″ knockouts with 3′ leads for easy installation
  • Features an optional mounting bracket for surface mount applications
  • Optional audible alarm and remote dry contacts
  • For use in 10 modes of protection (L-N, L-L, L-G optional, N-G optional)
  • Features a 5-year warranty

STXT Series:

The STXT Series is the most advanced of the STX series. It comes standard with EMI/RFI Filtering and surge capacities up to 200kA. It features TPMOV®, with line or load side installation flexibility, making it a great fit for a service entrance all of the way down to each distribution and/or branch panel.

Product features and benefits:

  • Designed with the industry leading Mersen TPMOV® technology
  • Premium 200kA surge capacity for longer life and higher single impulse withstand
  • Includes EMI/RFI filter for cleaner attenuation
  • Features a mounting hub and mounting feet for installation flexibility
  • Optional audible alarm and remote dry contacts
  • Up to 10 modes of protection (L-N, L-L, L-G, N-G)
  • Features a 10-year warranty

Save time and money and stay protected from unwanted surge spikes and equipment failures with the STX Series from Mersen. Interested in learning more about how they can protect your facility? Contact your French Gerleman Account Manager today!


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New Outdoor LED Lighting Surge Protection Solutions from Mersen

LED technology and lighting has taken over the market because of their efficiency, versatility, energy savings and longer life. But why is surge protection needed, particularly in outdoor applications? While they have countless benefits, the technology also has a number of drawbacks, including higher cost of implementation, more complex internal electronics and they are much more sensitive to overvoltages than traditional light sources.

To help extend the life of an outdoor LED luminaire, the use of overvoltage surge protection systems is a cost effective investment to ensure the ROI of LED projects.

Often times people associate SPDs with interior machinery, but with outdoor LED lighting, it’s important to protect your equipment, or your cost savings might go out the window. So what is a surge protection device (SPD)? A SPD connects upstream of the drive, complements the intrinsic immunity of the luminaire, creating a more robust protection against lightning and overvoltages. SPDs protect equipment by discharging the overvoltage to earth, therefore limiting the voltage reaching the equipment.

The three-stage SPD solution from Mersen

  1. Lighting Panel (SPD+POP series)
  2. Pole/Fusebox (STM SLIM series)
  3. Luminaire (STLB series)

Surge Protection in the Lighting Panel
This is the first stage of protection. A two-in-one combined (POP + SPD), it protects against permanent

or temporary overvoltages (POP) is the perfect complement to the typical first stage protection, a type 2 SPD in the lighting panel.

Surge Protection in the Pole/Fusebox

Mersen’s STM SLIM is the new range of LED arresters which provides a solution for installation in fuse boxes (located in the mast of the luminaire) with a DIN rail. It’s perfect for retrofitting.

Surge Protection in the LED Luminaires
These feature STLB Surge-Trap, the best in-line surge protection for LED lighting applications. A single device is suitable for single, split or three-phase applications; can be installed in series or parallel with the luminaire; features leakage current free technology and visual end-of-life indication.  The fastening flange allows the SPD to be installed upright or flat, depending on the space constraints of the luminaire.

Mersen Map

It is certified and suitable for worldwide installations.

Mersen’s Surge-Trap three stage LED solution is ideal in a wide range of outdoor lighting applications, including: street lighting, industrial lighting, public lighting, parking garages/surface lots, stadiums, tunnels and much more. For more information on Mersen’s Surge-Trap LED surge protection, give your Account Manager a call or contact us.


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Mersen New Product Launch: Surge Protective Devices

Your facility is full of expensive, important equipment that you rely on daily. Not only do down machines cost you time, they are expensive and frustrating for your team and customers. That’s why surge protection is a hot topic that you NEED to make sure is addressed.

What types of damage can a surge cause to a facility? The three main types are disruptive, dissipative and destructive.

  • Disruptive is when a surge enters an electronic component which interprets the valid logic command. This causes the system to lock-up and machines to malfunction, which leads to faulty output or corrupted files.
  • Dissipative damage is caused by a repetitive, pulsing of short duration energy, causing long-term machine or system degradation, leading to system replacement sooner.
  • Destructive damage is a high-level energy surge that immediately results in equipment at earlier intervals.

With a minimal investment, you can protect your sensitive equipment or entire facility from surge events. Mersen’s Surge-Trap product line offers a world-class suite of surge protection products designed to keep your facility protected and save you from costly, unscheduled downtime.

Mersen has created six new product lines to address all applications and target markets. They are:

  1. Surge-Trap STXH
  2. Surge-Trap STXR
  3. Surge-Trap STXP
  4. Surge-Trap STXT
  5. Surge-Trap STZ (Internal)
  6. Surge-Trap STZ (External)

Features and Benefits

All devices are Type 1 SPDs making them suitable for all applications from facility service entrances to individual equipment point-of-use. These surge protective devices are designed with the popular, industry leading, Mersen-patented Thermally Protected MOV (TPMOV) technology – the best performing, most reliable surge suppression technology on the market. It also features a wide range of surge capacities to fit any and all applications and target markets.

Each surge protective device is designed with the latest printed circuit board technologies and components for optimized footprint, cost and reliability. They feature options addressing the needs of new and retrofit facility installations, including LED status indicators, surge counters and disconnect switches.

Mersen surge trap

Nema surge

Why should you choose Mersen? Almost all Mersen SPDs feature their patented TPMOV technology, a fail-safe surge protection solution that eliminates the need for additional wiring, fuse components and costly installation time. As a result, Mersen offers the lowest cost, safest and most reliable surge protection products on the market. Their TPMOVs cover every nearly voltage need within your facility.

To see the full line of products, descriptions and features, you can download the PDF HERE.

While many people are familiar with the damage that a lightning strike can inflict, fewer people are knowledgeable about the dangers of indirect lighting strikes. In this video from Mersen, you’ll learn how their Surge-Trap SPDs can help protect you.

Are you new to surge protection or interested in learning more? Mersen offers education and collaborative product training annually with hands-on experience to learn more about their products. For more information, contact your French Gerleman Account Manager today.


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Featured Product: Mersen’s Medium Voltage Controllable Fuse – Breakthrough Arc Flash Protection

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Mersen’s Medium Voltage Controllable Fuse (MVCF) System is designed to mitigate the arc-flash hazard on the low-voltage side of a medium voltage transformer. The industry’s first fuse to provide normal short-circuit and overload protection while having the capability to open on command, this fuse is a cost effective arc flash solution with minimal installation downtime and ownership maintenance.

Mersen developed the MVCF in response to OSHA Code 29 CFR-1910 Subpart S, requiring employers to identify and analyze arc-flash hazards and provide adequate personal protective equipment (PPE). For many installations, the arc-flash energy is over 40 cal/cm2, which is too high for PPE, requiring owners to prevent access to those areas unless power is disconnected. This is typically unworkable and does not mitigate the hazard.  Visit Mersen’s Arc Flash Info Center for additional information.

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Features and benefits:

  • Fuses fit into existing clips and space. The retrofit can be completed in minutes, provided fiber optic cable is already in place.
  • Lowest-cost arc-flash mitigation solution. A turnkey installation of the MVCF will cost a fraction of other available alternatives.
  • Exceptional performance.
    • 50kA short circuit interrupt rating.
    • Fast response time mitigates the arc-flash energy to Category 2 PPE.
  • Low maintenance. Fuses are designed to last 20 years with no maintenance intervals, and the battery lasts for three years.
  • Flexible design interface. Designed to be used with a variety of conventional arc-flash detection devices and relays.
  • No nuisance-tripping. Actuator modules are programmed to ignore trip signals when primary current is below the fuse rating.
  • Automatically performs a weekly system check. Confirms continuity on all FO lines.
  • Minimal stress on other devices. The fuse element softens the voltage spike that occurs when opening. Alternatives may generate an excessive spike that could damage transformer insulation or upstream devices.
  • Small back-up power cells. The MVCF utilizes small batteries that fit inside the Controllable Fuse Actuator Module (CFAM) versus other solutions requiring multiple lead-acid car batteries

How does the MVCF’s Intelligent Fuse System work?

  • The Mersen MVCF operates like a normal MV fuse under short circuit and overload situations. When connected to an Arc-Flash detection system that is properly set up, the MVCF will open the circuit in time to limit the hazard to Category 2 PPE.
  • The Mersen MVCF System’s Interface Module (CFIM) is mounted in the low voltage area and accepts a trip signal from the customer’s existing arc-flash detection relay.
  • The CFIM immediately sends a signal over fiber-optic cables to the Actuator Modules (CFAM) attached to the bottoms of the fuses in the medium voltage cabinet.
  • The CFAM then causes a switch within the fuse to open. This shunts the current through a much smaller fuse element that opens the circuit in a controlled manner.

To learn how you can use Mersen’s MVCF to help cost-effectively mitigate arc-flash hazards, contact your French Gerleman representative.


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Meet Code Requirements with Mersen’s Fused Coordination Panelboards

Mersen’s Fused Coordination Panelboard (MFCP) is designed to meet requirements defined by the National Electrical Code (NEC) to protect critical power operations.

The MFCP provides a simple 2:1 coordination ratio with upstream Amp-Trap 2000 fuses, eliminating the need for a costly short circuit current study. Panels are provided with a default short circuit current rating (SCCR) of 200kA and provide overcurrent protection through a combination of a circuit breaker and a fuse. MFCP is a UL67 listed panelboard that utilizes commonly available class CC and class J fuses.

Combination rated circuit breaker and fuse for branch circuit protection ensures fuses will open only on short-circuits and the circuit breaker can easily be reset on common overloads. The circuit breaker is designed to operate on overloads up to two times their rating and the fuse over two times up to 200kA.
MFCPs can simplify the process in achieving code compliance for designers. Highlights include:

  • Easy selectivity ratios with upstream fuses
  • Resettable overload protectionPHP-Fused-Coordination-Panelboard-Door-Open_SMALL
  • Voltage: 120/208, 120/240, 277/480, 347/600
  • Main Bus: 250A or 400A,
  • MLO, Fused Main or Non-fuse Main disconnect
  • SCCR: 200kA
  • Surge Protection (SPD) optional
  • 20, 32 or 42 branch circuits
  • Standard 20″ wide
  • Feed through lugs optional
  • Surface mount
  • Uses commonly available class CC and J fuses


Selective Coordination is Simpler with MFCPs

Selective coordination is now simpler, less time-consuming and less costly thanks to Mersen’s Fused Coordination Panelboard (MFCP). Achieving selective coordination typically requires a costly short circuit current study. However with the MFCP, coordination can easily be determined with upstream Mersen fuses. MFCP utilizes Amp-Trap 2000® ATDR and AJT fuses for branch circuits. Simply maintain a 2:1 ratio with upstream Amp-Trap 2000 fuses and the system will coordinate. Many circuit breakers will coordinate easily with downstream fuses.

A system that is selectively coordinated will ensure that any fault condition is localized to the nearest overcurrent protective device. This increases system reliability and decreases downtime. Selective coordination is desired for all systems but is also mandatory per NEC for critical circuits:

  • 62 – Elevator Circuits
  • 27 – Emergency Systems
  • 18 – Legally Required Standby Systems

By localizing a fault to the nearest overcurrent device selective coordination prevents unnecessarily disconnecting other circuits in the system. An electrical system that utilizes Mersen fuses can simply be selectively coordinated by meeting the minimum amp rating ratios. By adhering to the minimum fuse ratios engineers and installers can save time and money because no complex coordination study is required.

Want to learn more about how Mersen’s Fused Coordination Panelboards can help with your selective coordination code compliance?  Ask your French Gerleman representative for more information today!


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Understanding and Avoiding an Arc Flash Hazard

More than 2,000 workers per year are sent to hospitals and burn centers with injuries due to arc flash injuries. That is a shocking number. But how can you avoid a terrible hazard like this from occurring at your facility?

Before you can understand how to avoid an arc flash, you must understand the problem. An arc flash is an explosive release of energy caused by a low-impedance connection between one phase of an electrical system and another phase, neutral or ground.

But what causes an arc flash? There are several scenarios that can cause this hazardous situation.

  • Coming close to a high-amp source with a conductive object, causing the electricity to flash over.
  • Dropping a tool or creating a spark can ignite an arc flash.
  • Any breaks or gaps in insulation.
  • Dust, corrosion or any other impurities residing on the surface of the conductor.
  • Equipment failure due to improper installation, substandard parts or even normal wear and tear over time can cause an arc flash.

To see some of these scenarios for yourself, watch Mersen’s Arc Flash mitigation product video to view test lab footage showing how their fuses reduce damage to equipment and PPE.

Now that you know what can cause an arc flash, how do you reduce the risk? The Mersen Arc Flash Info Center pulled together a great overview of ways to reduce the risk of arc flash in your facility. Here is a summary.

  • Be sure to have the correct fuses on hand. Out of stock and outdated fuses increase the potential for dangerous misapplications.
  • Provide safety training for your staff. Create customized training for various targeted audiences to help emphasize the importance of accurate fuse replacement.
  • Use finger-safe devices and low-voltage disconnect switches when possible. We recommend the Mersen UltraSafe fuse holders are the industry’s first finger-safe power distribution block.
  • Learn more about mitigating arc flash hazards. Mersen offers regional engineering seminars, many specializing in arc flash protection.

If you’re interested in learning more about what causes an arc flash and how to reduce the risk or an arc flash, give your French Gerleman Account Manager a call or contact us.