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© 2008 Eaton Corporation. All rights reserved.

FlashGardTM Motor Control Center

Electrical Safety Hazards

Design Philosophy

The Product

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Research studies say ….

• Five to 10 arc flash explosions occur in electrical equipment every day in the United States, according to statistics compiled by CapSchell, Inc., a Chicago-based research and consulting firm that specializes in preventing workplace injuries and deaths.

Based on the incidents reported … Unreported cases and “near misses” are estimated to be many times this number

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What is an Arc Flash?

Arc Flash

An Arc Flash is a dangerous condition

associated with the explosive release

of energy caused by an electrical arc

due to either a phase to ground or

phase to phase fault. This fault can

result from many factors, including

dropped tools, accidental contact with

electrical systems, build up of

conductive dust, corrosion, and

improper work procedures among

others

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What is Arc Flash Energy?

It’s expressed in calories per centimeter squared (cal/cm2)

where Calorie (cal) – Amount of thermal energy required to raise 1 gram of water’s temperature 1 degree C.

so Calorie/cm2 = Energy per unit of area

TO GIVE YOU A PERSPECTIVE:

• 1 cal/cm2 = the Exposure on the tip of a finger by a Cigarette Lighter in One Second

• One to Two cal/cm2 will cause a 2nd Degree Burn on Human Skin

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MCC’s

Motor Control Centers account for the second highest frequency of electrical accidents.

WHY???

Another known fact …

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MCC’s are worked on more than any

other electrical equipment when

energized

• Most feel comfortable working on them live

• Measurements are taken daily

• Maintenance work is performed daily

• While unit is energized to avoid downtime of critical equipment or processes

• Or on bench … but inserting and extracting the units are done live

Why MCC accidents occur?

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NFPA 70E 130.3 (B)

• Protective Clothing and Personal Protective equipment for application with a Flash Hazard Analysis

• Where it has been determined that work will be performed within the flash protection boundary by 130.3(A), the flash hazard analysis shall determine, and the employer shall document, the incident energy exposure of the worker (in calories per square centimeter).

• Flame-resistant (FR) clothing and personal protective equipment (PPE) shall be used by the employee based upon the incident energy exposure associated with the specific task.

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You Have Two Options…NFPA 70E, provides two methods for determining the flash hazard risk and the associated

PPE to be used:

1. Generic Hazard/Risk Guideline: Defines the PPE by the specific task and exposure based on a conservative fault/energy level assessment [NFPA 70E Table 130.7(C)(9)(a)]. This Hazard/Risk Category classification table is straight forward and simple to understand.

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You Have Two Options…NFPA 70E, provides two methods for determining the flash hazard risk and the associated

PPE to be used:

2. Arc Flash Analysis Method: Conducting a flash hazard energy analysis to determine the actual “Flash Protection Boundary” and the necessary PPE. This requires data such as equipment configuration, gap between electrodes, grounding type, short circuit fault current value, system voltage on input etc.

Category Cal/cm2 Clothing0 1.2 Untreaded cotton1 5 Flame retardant FR shirt and FR pants2 8 Cotton underwear, FR shirt and FR pants3 25 Cotton underwear, FR shirt, FR pants and FR coveralls

4* 40Cotton underwear, FR shirt, FR pants and double-layer switching coat and pants

* Output Categoryfor personel protective equipment (PPE)Source: NFPA 70E, Table 3-3.9.3

DETERMINING PPE HAZARD RISK CATEGORY

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• Wearing full (CAT4) PPE for every electrical task makes electrical equipment safer

Try working in PPE like this:

• Always shut down the Motor Control Center

The best practice… Sadly, this is not reality…Users often find this a lengthy and costly proposition jeopardizing production

Common Arc Flash Mythology

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Rajiv Kumar

MCC Product Manager

Fayetteville, NC

FlashGard™ Motor Control Centers

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What is Eaton’s FlashGard™ solution?

1. Maintain a “dead-front” door closed while inserting or removing MCC buckets

2. Insulate and Isolate current carrying bus and components

3. With the IT. door open - limit voltages in the work area below 120 volts

4. Lower the clearing time of the upstream breaker feeding the MCC

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What is the Eaton FlashGard™?

• FlashGard™ maintains a “dead-front” closed door while inserting or removing MCC stabs while ALL other MCCs require the door to be OPEN!!!

Standard MCC:

• De-energize bucket

• OPEN THE DOOR

• Disengage retention

• Yank bucket by hand

• Hope for no explosions

• Close door

• Move away hastily

FlashGard™ MCC:

• De-energize bucket

• Insert 3/8” square drive tool or remote racking tool

• Withdraw MCC stabs

• Once visual indicators indicate lack of power and bucket shutters are closed…

• Open the door

• Disengage retention

• walk casually away

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The Ultimate Design: Eaton’s FlashGard™MCC with RotoTract™

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What is the Eaton FlashGard™?

• FlashGard™ maintains a “dead-front” closed doorwhile inserting or removing MCC buckets

RotoTract™

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Let’s think about our competition’s supposed “Arc-Resistant”offering…ANSI C37.20.7 provides testing standards for Arc Resistant Switchgear. MCCs are NOT switchgear!!!!

Switchgear must have properly latched or secured covers, doors

There is no such thing as an “Arc Resistant” MCC!!!

How many MCC accidents happen with the doors and covers latched?

Arc Flash with theDoor Open

ANSI generalizes this at CAT 3!!!

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RotoTract™ Top Removed

RotoTractTM Assembly

Automatic Shutters

EATON

wins

AGAIN

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How RotoTract™ works

Bucket Position Indicator Connected

Test*

Withdrawn

* No TEST positionwith Freedom

Breaker must be open to access racking tool receiver

RotoTractTM

prevents stripping of the mechanism or overtorquing

Makes insertion of large size 4,5 buckets much safer. No more shoving buckets on to the vertical bus

Internal Shutter Indicator Open

Closed

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Completely enclosed connection of the stabs to the vertical bus in combination with insulated components makes the MCC virtually Arc Free

Stabs Extended

Stabs Withdrawn

RotoTractTM Stab Assembly

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Why Keep the Door ?

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Why Keep the Door ?THAT’S

IT!!!!!

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Why Keep the Door ?

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What is the Eaton FlashGard™?

Insulated and Isolated

current carrying bus

and components

Automatic Shutter

Labyrinth Vertical Bus

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Completely enclosed connection of the stabs to the vertical bus in combination with insulated components makes the MCC virtually Arc Free

Stabs Extended

Stabs Withdrawn

RotoTractTM Stab Assembly - How it works

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Why Shutters?

Automatic Shutters provide Isolation and Insulation.

• Provides personal protection by isolating and insulating the live bus should a MCC unit be removed or moved to the service position,

• i.e., a Hazard/Risk Category reduction from Level 2* to 0 [NFPA 70E Clause 130.7(D)(1)(h), specifically Table 130.7(C)(9)(a)].

• In addition, the shutters provide isolation which helps restrict an internal arc from spreading to the vertical bus [NFPA 70E Clause 130.7(D)(1)(h)].

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What is the Eaton FlashGard™?Freedom 2100 FlashGard MCC

Vertical Ground Bus

CPT mounted behind device island just like any Freedom

MCC bucket

120VAC Means no “TEST”Position in Freedom FG!

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The Freedom FlashGard™ Bucket

Power Stab Position

Connected

Disconnected

Handle Mechanism

Breaker

Racking Tool Receiver

Freedom Contactor

Unit Latch

C440 SSOL

Internal Shutter Position

Open

Closed

Pilot Device Island/ Panel

• Start, Stop, HOA

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Standard and Optional Features

• Standard• RotoTractTM Assembly

• Labyrinth Vertical Bus

• Insulated Horizontal Bus

• Optional• Bottom Plates (Stnd on NEMA 12)

• Vertical Bus Barrier

• Rodent Barrier

• Remote Racking Device

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FlashGard™ Remote Racking

Remote Racking “wired” Accessory• Accessory to perform RotoTract™

racking safely behind NFPA Arc Flash boundaries

• 120 VAC motor driven

• Standard Wall Plug

• Mounts to RotoTract™ Mechanism

• Wired pendant station for “rack-in”/ “rack-out” operation.

• Mounting offset bracket to clear device panel

Accessory Mounting

Holes

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VoltageVision™Presence or absence of voltage indicator

Motor Guard™• Motor Guard is a patented motor

testing and protection system AUTOMATICALLY monitors motor insulation breakdown

FlashGard™ Door Accessories

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FlashGard™ Aftermarket

• Freedom FlashGard and IT FlashGard

• Freedom/ Advantage/ Five-Star MCCs - FFG – Drop in to any 2100 w/ Labyrinth Vertical Bus

- Non Labyrinth requires EESS Barrier retrofit

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