Designing for Safety: ABB Medium Voltage Switchgear and MCC

Transcription

1 February, 2013 Designing for Safety: ABB Medium Voltage Switchgear and MCC ABB Inc. January 23, 2013 Slide 1

2 What is an Arc Flash? The result of a rapid release of energy due to an arcing fault between phases, neutral or a ground. An arc arises when at least part of the current passes through a dielectric, usually air Maximum peak power up to 40 MW Arc temperature up to five times the surface temperature of the sun (20,000 C) Light intensity more than 2000 times that of normal office light Volumetric expansion approximately 40, Temperature of the sun surface is about 5000 C. ABB Group October 13, 2011 Slide 3

3 PSI Pressure Buildup vent flap opens enclosure rupture conventional SafeGear time (ms) Pressure measurements Successful SafeGear test ABB Group October 13, 2011 Slide 15

4 Arc Flash Danger Statistics Currently, OSHA lumps Arc Flash incidents in with electrical incidents. A recent survey showed that 5-10 people per day go to burn centers due to arc flash incidents that does not include those going to local and regional hospitals That is people a year in the US! With the high mortality rate of burn injuries, this can translate to hundreds of deaths a year IEEE did a study with a large utility and over the last 53 years, they have had 1 arc flash incident every 18 months. ABB Group October 13, 2011 Slide 5

5 Causes: Causes and Effects of an internal Arcing Fault Improper maintenance, mechanical, and interlock failures Failure to follow procedures Gradual component or insulation breakdown Foreign objects, rodents, snakes, etc. Effects: Pressure increase in an enclosed compartment Function of arc voltage, current, number, and duration of arcs, volume Rapid onset (10-15 ms) results in explosive forces Thermal effects, hot gases Catastrophic to nearby personnel and equipment ABB Group October 13, 2011 Slide 7

6 Industry Recognized Arc-Resistant Standards OSHA 29 Code of Federal Regulations (CFR) Part 1910, Subpart S NFPA 70E-2004, Standard for Electrical Safety in the Workplace IEEE , Guide for Arc Flash Hazard Analysis IEEE C , IEEE Guide for Testing Medium-Voltage Metal-Enclosed Switchgear for Internal Arcing Faults ABB Group October 13, 2011 Slide 9

7 Characteristics of Arc Resistant Switchgear Designs Robust construction to direct gases to exhaust chambers Vent flaps designed to open under pressure and safely expel gases Special ventilation Under normal conditions, open to allow air to flow Under arc fault conditions, slams shut to prevent exit of gases Double wall construction with 3/16 air gap is very effective in resisting burn through Closed door racking and operation of circuit breakers, PT s, CPT fuses

8 Modular Design Bolted construction enables faster replacement and modification in the field Allows for easy replacements, repairs, and specialized configurations Maintains the smallest, compact product ABB Group October 13, 2011 Slide 21

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10 Classification of Arc-Resistant Switchgear per IEEE C : Type 1 arc-resistant construction at the front only Type 2 arc-resistant construction at the front, back, and sides Annex A addresses suffixes B and C Type 1C Type 1, with arc-resistance designs or features between adjacent compartments Type 2B Type 2, retaining the arc-resistant characteristics with LV instrument compartment door being open Type 2C Type 2 with arc-resistance features between adjacent compartments, switchgear survives with a minimum damage Type 2BC The ultimate in protection combines types 2B and 2C

11 1 Each primary compartment breakers, auxiliary transformers, main bus, and primary cable entrances are designed with internal hinged flaps or vents to allow over-pressure and hot gases to escape in a carefully controlled manner through roof mounted plenum exhaust ducts away from nearby personnel at the front, rear or sides of the switchgear. 2 Roof-mounted hinged flaps are engineered to open quickly as pressure increases in an arc fault condition. Venting flaps and chimneys release excessive pressure during an arc event. Front, side and rear structures maintain their integrity.

12 Location of Flaps and Vents in SafeGear ONE-HIGH 1200A 1200A W/2 VT UNITS TWO-HIGH 1200A ABB Group October 13, 2011 Slide A W/FUSED CPT 2000A W/1 VT UNIT ONE-HIGH 3000A

13 SafeGear Patented Internal Collection Chamber ABB Group October 13, 2011 Slide 32

14 Plenum Benefits Channels gases out of PDC Provides room for flap operation Allows gases to expand Protects cable trays Maintains weather protection Allows lower building height Plenum PDC ceiling Two-high SafeGear PDC Aisle ABB Group October 13, 2011 Slide 34

15 Plenum Design Sealed duct across top of switchgear, covering all vent flaps Sized and shaped to minimize turbulence and back-pressure Allows room for cable trays and conduit entry Channels gases safely out of building, through wall penetration and vent ABB Group October 13, 2011 Slide 35

16 Plenum End Flap Flaps normally closed Opens with pressure in case of arc fault ABB Group October 13, 2011 Slide 36

17 Medium Voltage Motor Control Center

18 Technical Specifications MOTOR CONTROL / TWO-HIGH Contactor: 400 A Main Bus: 2000 A (All measurements are in inches.) SafeGear medium voltage motor control Advance medium voltage motor control

19 Product Description Vacuum Contactor Module Ratings Unique Racking System The vacuum contactor module is a new design with operator and maintenance personnel in mind. It incorporates distinctive features for ease of installation, operational safety and maintenance simplicity. Contactors are rated at 400 A and 720 A and comply with UL 347 temperature rise requirements. Two-high design can be accomplished using 400 A contactors with no derating. The racking system is unique and features a two-position, (Connected-Test/Disconnected) closed-door system for all contactors. It also includes a fully automatic secondary disconnect system. The racking system is integral to the contactor. The contactor/ enclosure system includes all necessary interlocks to assure proper sequencing and safe operation. For improved safety, the interlocking system prohibits racking while the door is open. The contactor can only be racked into the Connected position with the door closed while maintaining the integrity of arc resistance. The contactor enclosure includes stationary support bushings and primary contacts for engagement with the contactor. Standard padlock provisioning is provided for securing the contactor in place. Additional padlocking provisions available (optional). Easy access to the Contactor Module improves maintenance and operation. Superior safety is provided by the closed door racking system. SafeGear medium voltage motor control 33 Advance medium voltage motor control

20 Product Description Toc Actuator Optional TOC contacts (Run & Test Service) are actuated by the front of the panel as the contactor moves in and out of the connected position. Contactor Grounding A stationary ground contact interacts with the ground contact of the controller unit. Ground connection is made prior to coupling of the primary or secondary contacts and is continuous during the racking operation. Interference Blocking The contactor enclosure has interference blocking to prevent the insertion of improperly rated controllers. SafeGear medium voltage motor control 34 Advance medium voltage motor control

21 Product Description Vacuum Contactor Truck Assembly The vacuum contactor and power fuses are mounted on a fully-withdrawable truck assembly similar to the ADVAC TM circuit breaker used in SafeGear and Advance metal clad switchgear. The truck assembly eliminates the need for an isolation switch thereby reducing the number of moving parts and simplifying the handling. The operation is identical to MV switchgear. Front view, Back view of contactor module A lifting device latches to the contactor module for simple and safe extraction of the contactor. The height of the tray on the lifting device can be adjusted to fit the compartment height. Maintenance work, such as exchange of fuses, can be conducted with the contactor locked in place on the lifting device. Other maintenance is simple and safe because all parts requiring service are mounted on the truck for inspection away from energized equipment. These parts include the vacuum bottles, power fuses, the control power transformer and its fuses, auxiliary switches and the ground contact. The blown fuse indicator on each fuse is visible from the front of the assembly with the contactor in the Test/Disconnect position and with the door open (see technical specifications for more information). SafeGear medium voltage motor control 36 Advance medium voltage motor control

22 Low Voltage Instrument Module Dedicated low voltage compartment for protection and control devices Low voltage compartment completely isolated from the high voltage components Devices and control switches mounted on low voltage door for readability and access Various configurations allow for 19, 38, & 57 tall modules,

23 MAIN BUS Main bus ratings are available in 1200 A, 2000 A & 3000 A Flame-retardant insulation provides resistants to tracking Silver or tin plated for aggressive environments Removable/reusable boots for protection and ease of inspection Bus is front accessible via low voltage compartment Main Bus Access AdvanceTM medium voltage motor control center (MVMCC) is 100% front accessible a 5

24 Auxiliary Primary Modules ABB potential transformer modules accommodate industryleadingq ABB VIY-60 kv BIL potential transformers and are rack mounted in a 19 module Each standard module accepts up to three PTs with line-to-line (L-L) or line-to-ground (L-G) connections Optional 75 kv BIL type PTs accept up to two transformers mounted in a 38 module PTs are automatically grounded when withdrawn to discharge any residual current Standard 60 kv BIL PTs

25 SafeGear and Advance do not incorporate an internal arc chamber. The roofs of the lower and upper contactor compartments have permanent ventilation for hot gases. The chambers are approximately 17 inches deep and either 19, 38, or 57 inches tall. It is not necessary to have a 57 inch chamber in a line up to exhaust hot gases through the roof.

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27 Rating Contactor Rating Interrupting ratings at 2.4, 5.0 & 6.6 kv Short time current CONTACTOR RATINGS Value 400 A 720 A NEMA unfused 25 / 50 / 60 MVA 30 / 60 / 85 MVA NEMA fused 200 / 400 / 570 MVA 200 / 400 / 570 MVA 30 sec 2,400 A 4,320 A 1 sec 6,000 A 10,800 A 10 ms 85 ka (peak) 85 ka (peak) Mechanical life, lactched/ unlached* 250,000 / 2,500, ,000/1,000,000 Switching frequency (per hour) 300 / / 600 latched / unlatched Electrical life* 250, ,000 Impulse widthstand 60 kv 60 kv Dielectic strength 22 kv -1 minute 22 kv -1 minute Maximum voltage level 7200 V 6900 V Contactor close time (max) 4.8 cyc 60 Hz (80 ms) 4.2 cyc 60 Hz (70 ms) Contactor open time (max) Control ratings: 1.5 cyc 60 Hz (25 ms) 2.1 cyc 60 Hz (35 ms) Contactor control voltage Std: 120 V AC 50/60 Hz V AC / V DC Option: 240 V AC / 125 V DC / 250V DC Pickup voltage AC or DC 85% (hot) 70% (cold) 85% (hot) 70% (cold) Dropout voltage AC or DC 50% (hot) 40% (cold) 50% (hot) 40% (cold) Burden closing 670 VA (AC) 700 W (DC) 840 VA (DC) 875 W (DC) Burden holding 85 VA (AC) 85 W (DC) 48 VA (AC) Auxiliary contact 3NO, 3NC 3NO, 3NC 2NO, 3NC (lachted) Max voltage 600 V 600 V Continuous current 10 A 10 A Ambient ratings Making capacity 7200 VA 7200 VA Breaking capacity 720 VA 720 VA Altitude without derating 6600 ft 6600 ft Temperature -5 to 40 C -5 to 40 C Humidity 45-85% 45-85% Vibration 20 Hz 1 G 20 Hz 0.5 G Frames per shipping split 3 3 Arching time 10 Milliseconds 10 Milliseconds Dimensions (1200, 2000 A bus) 30 x 40 x x 40 x 95 (W x D x H inches) (3000 A bus) 30 x 48 x x 48 x 95 Arrangements 2 High 1 High Voltage System Motors Squirrel Cage 1,750 2,250 3,000 4,500 2,500 3,000 4,500 6,000 Sychronous Motor (0.8) 1,750 2,250 3,000 4,500 2,500 3,000 4,500 6,000 Sychronous Motor (1.0) 2,000 2,500 3,500 5,000 3,000 3,500 5,000 7,000 Transformer (kva) 1,500 2,000 3,000 4,000 2,500 3,500 4,500 7,000 Capacitor (kvar) 1,500 2,000 2,000 2,000 2,000 2,000 2,000 2,000 * Maximum required for testing. Actual life is greater under normal operations and conditions.

28 REP LAC E WHE N WARNING: OPE N CL OS E! WA RNI N G! REPLACE ALWAYS COMPLETE FUS EAC H OPERATI ES ON WHE (UP/DOW N) N PIN IS OUT WARNING V er if y al l d o or a nd pa ne l WITHOUT STOPPING. bo lts ar e fu ly se at e d b ef or e op er at in g t hi s eq ui pm ent. R ef er t o I nst r uction B ook f or det ailed inst r uct ions WARNING R ef er t o I nst r uction B ook f or det ailed inst r uct ions WARNING: HA ZA R D O F E LE C TRI C A L SH O C K OR BURN TU SUPPLYING R N O FF P O WE R THI S E QUI P M E N T BEFORE W O R KI N G INSIDE OPE N CLOSE! WARNING! ALWAYS COMPLETE FU SES EAC H OPERATI ON (UP/DOW N) WI TH OU T S TOPPI N G. PIN IS OUT HA ZA R D O F E LE C TRI C A L SH C K OR TU RBURN N O FF P O WE R SUPPLYING THI S E Q UI P M E N T BEFORE W O R KI N G INSIDE WARNING V er if y al l d o or a nd pa ne l bo lts ar e fu ly se at e d b ef or e op er at in g t hi s eq ui pm ent. WARNIN G: R ef er t o I nst r uction B ook f or det ailed inst r uctions OPEN CLOSE! WA RNI N G! REP LAC E ALWAYS COMPLETE FU SES EAC H OPERATI ON (UP/DOW N) WHE N WI TH OU T S TOPPI N G. PIN IS OUT REP LAC E WHE N WARNING V er if y al l d o or a nd pa ne l bo lts ar e fu ly se at e d b ef or e op er at in g t hi s eq ui pm ent. R ef er t o I nst r uction B ook f or det ailed inst r uct ions WARNING: HA ZA R D O F E LE C TRI C A L SH C K OR TU RBURN N O FF P O WE R SUPPLYING THIWS OERQKI UINPG MINSIDE E N T BEFORE OPEN CLOSE! WA RNI N G! ALWAYS COMPLETE FU SES EAC H OPERATI ON (UP/DOW N) WI TH OU T S TOPPI N G. PIN IS OUT Typical Arrangements [1016.0] [1016.0] [2413.0] [254.0] [762.0] [965.2] [482.6] [965.2] [115.6] [165.1] [115.6] [44.5] [165.1] [115.6] OPENING FOR POWER CABLE/CONDUIT BOTTOM COMPARTMENT [119.0] OPENING FOR POWER CABLE/CONDUIT TOP COMPARTMENT OPENING FOR CONTROL CABLE/CONDUIT [136.5] [965.2] [1447.8] [359.1] [44.5] [165.1] [187.0] OPENING FOR POWER CABLE/CONDUIT BOTTOM COMPARTMENT OPENING FOR CONTROL CABLE/CONDUIT Cable Entrance, Top [1447.8] [965.2] [136.5] [359.1] [44.5] [165.1] [187.0] OPENING FOR POWER CABLE/CONDUIT BOTTOM COMPARTMENT OPENING FOR CONTROL CABLE/CONDUIT [762.0] [762.0] [762.0] CONTACTOR 400A LOW VOLTAGE INSTRUMENTATION COMPARTMENT CONTACTOR 400A V er if y al l d o or a nd pa ne l bo lts ar e fu ly se at e d b ef or e op er at in g t hi s eq ui pm ent. Motor Control - Two High Approximate Weight LB LOW VOLTAGE INSTRUMENTATIO N COMPARTMENT CONTACTOR 400A Motor Control - One High Approximate Weight LB Front View LOW VOLTAGE INSTRUMENTATION COMPARTMENT CONTACTOR 720A [254.1] Motor Control - One High [254.1] [762.0] FOR MAIN BUS 3000A " [330.2] Approximate Weight LB MAIN BUS 1200A & 2000A MAIN BUS 1200A & 2000A MAIN BUS 1200A & 2000A [117.2] OPENING FOR POWER CABLE/CONDUIT TOP COMPARTMENT OPENING FOR POWER CABLE/CONDUIT BOTTOM COMPARTMENT [119.0] [119.0] OPENING FOR CONTROL CABLE/CONDUIT OPENING FOR POWER CABLE/CONDUIT BOTTOM COMPARTMENT OPENING FOR CONTROL CABLE/CONDUIT [127.0] OPENING FOR POWER CABLE/CONDUIT BOTTOM COMPARTMENT OPENING FOR CONTROL CABLE/CONDUIT [762.0] FOR MAIN BUS 3000A " [330.2] FOR MAIN BUS 3000A " [1092.2] FOR MAIN BUS 3000A " [1092.2] [141.3] [141.3] [141.3] Cable Entrance, Bottom

29 ABB Oy January 23, 2013 Slide 2