© 2008 Eaton Corporation. All rights reserved.
FlashGard
TM
Motor Control Center
Electrical Safety Hazards Design Philosophy The Product
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
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
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MCC’s
Motor Control Centers account for the second highest frequency of electrical accidents.
WHY???
Another known fact …
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
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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
.
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
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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 Clothing 0 1.2 Untreaded cotton
1 5 Flame retardant FR shirt and FR pants 2 8 Cotton underwear, FR shirt and FR pants
3 25 Cotton underwear, FR shirt, FR pants and FR coveralls
4* 40
Cotton 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
•
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
11 11 Rajiv Kumar
MCC Product Manager Fayetteville, NC
FlashGard™ Motor Control
Centers
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
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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
The Ultimate Design: Eaton’s FlashGard™
MCC with RotoTract™
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What is the Eaton FlashGard™?
•
FlashGard™ maintains a “dead-front” closed door
while inserting or removing MCC buckets
RotoTract™
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 the
Door Open
17 17
RotoTract™ Top Removed
RotoTractTMAssembly Automatic Shutters
EA
TO
N
wi
ns
AG
AI
N
How RotoTract™ works
Bucket Position
Indicator
Connected Test* Withdrawn * No TEST position with FreedomBreaker must be
open to access
racking tool receiver
RotoTract
TMprevents 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 Closed19 19
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
RotoTract
TM
Stab Assembly
21 21
Why Keep the Door
?
THAT’S
IT!!!!!
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What is the Eaton FlashGard™?
Insulated and Isolated
current carrying bus
and components
Automatic Shutter Labyrinth Vertical Bus
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
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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)].
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”
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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
Standard and Optional Features
•
Standard
•
RotoTract
TMAssembly
•
Labyrinth Vertical Bus
•
Insulated Horizontal Bus
•
Optional
•
Bottom Plates (Stnd on NEMA 12)
•
Vertical Bus Barrier
•
Rodent Barrier
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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
VoltageVision™
Presence or absence of voltage indicator
Motor Guard™
•
Motor Guard is a patented motor
testing and protection system
AUTOMATICALLY monitors motor
insulation breakdown
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