Electrician. Handbook L&T SWITCHGEAR SAFE & SURE

Transcription

1 2007 L&T SWITCHGEAR SAFE & SURE Electrician Handbook

2 The assurance of a leader Larsen & Toubro Limited (L&T), India's largest manufacturer of low tension switchgear, now offers the most comprehensive range to suit applications for the Building Segment. L&T s switchgear conform to the latest international standards and is comparable with the best in the world. Electrical from L&T for the Building Segment are dependable, easily available and carry the assurance of L&T backed by a strong service capability that extends nationwide. The need for safe electrical for buildings is critical because it touches each and every individual directly - be it at a commercial mall, a cinema house, a residential complex, an educational institution, a place of worship, an airport lounge, a railway station, a bus station. Unsafe electrical in these buildings expose us to potential risks of electrical shock, fire, electrical failure. That is why buildings need electricals that are safe and sure. And if these electrical are aesthetically pleasing, that an added advantage! That is why, for your buildings, you should insist on L&T's electrical. Building Electrical from L&T provide you with: greater safety, higher reliability, assured performance and aesthetically appealing designs. Personal Details Name: Address (Office): Phone: Mobile: Fax: Address (Resi): Phone: Electrical Supervisor Licence No: Vehicle Registration No: Driving Licence No: Bank Pass Book No: Blood Group: In Emergency, Contact: Phone: General:

3 Contents Page No. Modular devices - Tripper Range Modular devices - Hager 6 Wire Range 7 MCBs & Necessity of Earthing 8 RCCBs 9 Sensitivity for RCCBs & its Selection 0 Surge Protection Devices -2 Control & Automation - Selection chart for Typical Domestic Loads 6 Details of Max. Short circuit current as per transformer kva 7 Selection chart for motor applications 8 Cable selection chart 9 Conduit sizes 20-2 System designing 22 First aid for electric shock 2-2 Modular Devices - Tripper Miniature Circuit Breaker Conforms to latest global standards like IS 8828, EN / IEC Carries CE and ISI marking and KEMA certification Breaking capacity of 6 ka throughout the range Available in B curve in SP & DP and C Curve in SP, DP, TP & FP versions from 6 A to 40 A ratings Unique - True Contact Indication shows actual status of contact Low power loss - almost 0% of the values prescribed by IEC Terminals are suitable up to sq.mm wire, with provided with of Dual Termination facility No line-load bias Isolator Conforms to global standards like IS 947, EN / IEC Carries CE marking and KEMA certification Available in range of 40 and 6 A in DP, TP and FP versions Suitable for AC22-A utilization category Finger-proof terminals IP20 degree of protection Ergonomically designed, profiled for superior cooling and manufactured with fire retardant material Earth Leakage + Miniature Circuit Breaker (EL+MCB) Provides in protection against Earth leakage, Short circuit and Overload. It also avoids excessive metering due to leakage Conforms to global standards like IS 2640, EN / IEC Carries CE and ISI marking Available in DP & FP versions in the range of 6 to 6 A with 0mA or 00mA or 00mA sensitivity Truly current operated operates even at nominal volt Featured with neutral advance mechanism Operation even in case of neutral failure Distribution Boards - Tripbox Available in aesthetically pleasing ivory colour to suit the interiors of buildings and can be supplied in different colour for bulk requirements Readily available in IP0 & IP42 degree of protection Distribution boards are suitable for flush and surface mounting Ready to use DBs - provided with 00 A phase busbar, wire sets, earth & neutral bars as standard Provided with removable top and bottom gland plates with adequate knockout for easy wiring For bottom entry, neutral bar can be shifted to bottom for comfortable wiring TPN DBs will have provision to accommodate 6 MOD incomer Easy installation and flexibility in usage

4 L AF SU L A FE & S U O H O L L Modular Devices-Hager Wires & Cables Miniature Circuit Breakers (MCBs) High breaking capacity of 0 ka Protects against overload and short circuits in domestic, commercial and industrial electrical distribution systems Available in SP, DP, TP & FP versions in B, C and D curve, widest rang from 0. to 2 A ratings Two position DIN rail clips allows faster installation Suitable for DC applications Conforms to latest standards IEC: 60898, IEC: 60947, IS: Accessories for MCBs and RCCBs Auxiliary contact ( NO+NC) Trip alarm contact Shunt release Under-voltage release Locking kit Flush-mounting kit Residual Current Circuit Breakers (RCCBs) Available in DP and FP versions in 2 A, 40 A, 6 A and 00 A ratings with 0 ma, 00mA and 00mA sensitivity No nuisance tripping Conforms to IEC 6008 RCBOs Offers in protection against earth leakage, short circuit and over load Rating: 6 A to 2 A in 2 pole with 0 ma and 00mA sensitivity Breaking capacity 4.kA Conforms to IEC 6009 FR House Wires Flat Cables Wires for industrial, commercial and domestic applications Voltage grade up to 00V Conforms to IS standards Complete safety ensured Insulation types available for all wires are Flame Retardant (FR) Flame Retardant Low Smoke (FRLS) Zero Halogen Flame Retardant (ZHFR) Heat Resistant (HR) House Wires Made of annealed copper conductor Conforms to IS standards The insulation used is FR PVC compound for additional safety Twin coating for superior insulation Range : 0.7 sq.mm to 2 sq.mm Flat Cables The cables are rigid and withstand all adverse conditions Made of bright plain multi-strand annealed copper conductors Available in 00 meter coils and drums of 00 and 000 meters Range :. sq.mm to 70 sq.mm Also available: earth-leakage relays and voltage surge devices Distribution Boards A comprehensive range of insulated and metal distribution boards for domestic, commercial and industrial applications All components comply with the latest standards Wide range of accessories for additional safety and flexibility Plug and socket DBs TPN and SPN DBs Vertical TPN DBs Phase changeover DBs Phase segregated DB Flexible Wires Telephone Cable The L&T Advantage Technology Raw Material Unmatched service Stringent quality Top ranking company Advanced know-how and state-of-the-art manufacturing processes High quality raw material Pre and post sales service backed by a nationwide network L& T ES AF & S U RE 2 P A I R L & T Comprehensive quality assurance that exceeds industry standards & T S E & R E 7 M R G6F & T &T S R E 7 H M RG F &T Automation & Control Devices Isolators, two-way / centre-off changeover switches Modular electro-mechanical / digital time switches Time lag and twilight switches Modular bells and buzzers Electronic thermostats Dimmers and dimming systems Analog voltmeter and ammeters Co-Axial Cable Flexible Wires Single and multi-core wires are available Suitable for industrial wiring applications Available in standard length of 00 meters coil Range : 0. sq.mm to 000 sq.mm The assurance of one of India's most reputed companies 2

5 Technical Specification Why use an MCB? MCBs are safety devices used to protect electrical installations from overload and short circuit. They switch off the circuit automatically, thus protecting from electrical fires. Advantage over conventional / rewireable fuse For MCBs, power supply can be restarted by just switching on the MCB, whereas replacing a blown fuse between live, current-carrying points is potentially dangerous, especially in the dark. Range Conforms to the latest version of the international Standards IEC / 200 & IS 8828 : to 2 A,, 2, & 4 pole with 0 ka breaking capacity. 6 to 40 A SPN MCB in one module size. Methods of providing earth leakage protection RCDs can be installed in two ways :-. Whole house protection 2. Selective protection Whole house protection is provided typically by a consumer unit where RCD device serves as the main incomer switch. Although very popular, this suffers from a disadvantage : all circuits are disconnected in the event of fault. Selective protection can be provided by associating the RCD with identified high risk circuits by adopting one of the following methods.. Split busbar consumer unit All circuits are fed via an isolator and selected circuits fed additionally via the RCD. Typical circuits fed direct are lighting, freezer and circuits fed via the RCD are socket outlets, garage circuits, geysers and kitchen outlets. This concept minimizes inconvenience in the event of fault. 2. Whole ring circuit A 0mA device adjacent to the consumer unit which provides protection for the downstairs ring circuit, provides an easy installation with protection for all associated socket outlets. This represents the best solution for upgrading existing installations. Nuisance tripping All Tripper / Hager, ELMCB / RCDs incorporate technology preventing the risk of nuisance tripping due to transient voltages (lightening, line disturbances on other equipment) and transient currents (from high capacitive circuit). Why use an RCCB? RCCBs are devices which protect the user from the harmful effects of electric shocks. These function by detecting the residual current, comparing the value with the rated residual operating value and opening the protected circuit when the residual current exceeds this value. 4

6 RCCBs / RCBOs Hi - version - Hager These can be used either individually or as an incomer to an MCB system. RCCBs with an inbuilt MCB called RCBO are devices which protect electrical installation from overload, short circuit and earth leakage faults. Connection diagram phase 4 wire system supply phase wire system supply phase system supply RCCBs / RCBOs - Hi version : The Hi-version RCCBs are designed to reduce unwanted tripping due to transient currents & voltages on account of lightening (8/20 current wave), flourescent lamps (400 Hz over voltage) operation of electronic products like computers / dimmers and industrial electronic products like drives. This has the capability to detect to sinusoidal and direct earth leakage currents. use use The human body's reaction to electric shock Control & Automation - Hager When electrical shock currents, pass through the human body, the nervous systemis thrown out of gear. This causes the body to react to the passage of current through it as follows : ma - a tingling sensation is felt Contactors Used for remote switching and control of power circuits. Available from 20 A to 6 A for AC Utilization Category. Sensitivity and Selectivity RCD 0mA 00mA 00mA 0-mA - muscle spasm and tightening occurs 20-0mA - the heart may fibrillate; severe shock is felt. >0mA - lethal. Fibrillation of the heart occurs Application personal protection domestic installation limited personal protection building / fire Twilight Switches Used for street, display lighting, illuminated signs, etc. Devices control by photo electric cell which measure light level, and in conjunction with relay are used to ON / OFF lighting circuit (in relation to natural light). Available in two sensitivities to 00 Lux and 0 to 2000 Lux. 6 7

7 Control & Automation - Hager Surge Protection Devices - Hager Time lag Switches Used for showrooms, multi storied buildings. Device controls lighting circuits with automatic switch - off after pre - set time (delay adjustable from 24 sec. to 2 min.) Rated for 6 A, 20 V AC and suitable with push buttons only. Dimmers & Dimming System Modular devices used for control of lighting levels in domestic premises, software offices, large corridors, conference halls and hotels. Control is localised. Remote is possible by associated Push Buttons. Separate dimmers are available for control of incandescent, halogen with standard or electronic ballast and flourescent lamps. Stand - alone dimmers for 600 W and 000 W, while control of 000 W can be possible by using master and slave combination. 2 - Way / centre-off changeover switches Used for changeover from one source of supply to another with centre - off position e.g. MSEB to DG supply changeover. AC 2 A utilisation category and suitable for use on 0 V DC. Available in 2 - Pole 2 & 40 A and 4 - Pole 40 A version. Voltage transients are mainly caused by switching events externally and internally Externally by :- Switching of transformers Switching of breaker and capacitor bank Large induction motors Speed controllers on motors Internally by :- Power Surges In low voltage AC power circuits, surges have two origins lightning or switching events. Voltage transients Lightening When lightening strikes on or near a primary circuit, it produces a transient voltage which is transmitted through a transformer to your secondary circuit. When lightening strikes on or near the secondary circuits, it results in an even higher surge to your equipment. Fluorescent, mercury / sodium discharge lighting Switching of compressors Air conditioners, commercial and domestic Washing machines In fact any inductive load will cause an increase in the line voltage at the time of switch off. As the fully excited magnetic field is collapsed due to switch off a very high voltage will be generated which may destroy sensitive electronic equipments. Surge is defined as voltage above 2 V (on a 20V Line) for a half cycle or longer. Power surges are bound to occur, but there is a way to offer protection for electrical and electronic equipment used in business. A surge protector is exactly the device that offers protection for the above equipment from transient over voltages. It can absorb and dissipate thousands of joules of energy. 8 9

8 Surge Protection Devices - Hager Surge Protection Devices - Hager SPD working :- The SPD responds to the transient over voltage by changing from its normal high resistance to low resistance and conducting surge current to ground. This current, and the resistance of the protector results in a discharge or residual voltage across the protector. This same voltage is seen by the protected equipment and defines the protective capacity of the surge protector. Damages caused by Transient over voltage - Disruption Degradation Damage Downtime SPD Standards :- Class I : 0/0 s impulse, lightning arrestors Spark gap technology, Up (residual voltage) - 4 kv / 7 kadiverting capacity to be used as main protection when there is a lighting rod near the installation. Our Products of class I are : SP7 Class II : 8/20 s impulse, over voltage protection, Varistors & GDT Up around <2. kv / 6 kadiverting capacity Our products of class II are : SP40D, SP440D. How to choose SPD :- Risk assessment What is the type of equipment? What costs the protected device? What is the risk of downtime? Is the protected material assured? Is the region exposed to lightening? Is there a lightening rod nearby the installation? What is the type of earthing system used TT, TN-S,TN-C, IT? Type of network (, 2 & phase)? What is Un (nominal working voltage) of the network? Any data network or telephone line? Caution: Use MCB or fuse as a backup protection for the SPD. * For further details on the product and installation guidelines, refer to our Technical Guide (on Hager Products). * In case of Electric Shock. Class III : Hybrid impulse, over voltage protection, Up < kv / 24 ka diverting capacity Our Products of class III are : SP208 The ability of a surge protector to handle a given amount of energy reflects its ability to survive. And to continue to protect the equipment, surge after surge it is most important to choose the proper surge protector. No protector can survive a direct lightening strike. 0

9 Selection chart for typical domestic loads S.No. Items Load/Wattage MCB rating Fan Lamp, Tubelight Room Heater Water Heater 8 ltrs ltrs 60 ltrs Immersion Heater Hot Plate-single Iron-Nonautomatic Automatic Mixer / Juicer TV / VCR / VCP Music system Refrigerator 6 ltrs 28 ltrs 0 ltrs Toaster Vacuum Cleaner Washing Machine without heater with heater Water Cooler Desert Cooler Oven Electric Kettle Air Conditioner ton. ton 2 ton Hair Dryer Microwave Formula for Calculations : Incomer Rating : Single Phase = 60W 40W 200W W W W 000W 000W 00W 000W 00W 200W 200W 400W 600W 70W 00W 400W 00-00W W 700W 00W 70W W 00W 2000W 000W 800W Total Load in Watts 20 volts Three Phase = Total Load in Watts x20 volts The given data is only for guidance and may vary for different manufacturers * * A 0 A 20 A 2 A 6A 6A A 6A 2A A A A 4A 6A A A 0 A 2 A 6A 2A 6A 7. A 0 A 6 A 6 A 7. A 6A Transformer Rating kva Max. Short Circuit current as per Transformer kva Full Load Current at 4 V Max. Short Circuit Current A (ka) 4% impedance % impedance

10 Motor Rating 4V, phase Selection table for motor application Full load current approx. Relay range Recommended back-up MCB 'C' Type 'D' Type hp kw amp. amp. amp. amp NC06N NC0N NC0N NC6N NC6N NC6N NC20N NC2N NC2N ND0N ND04N ND06N ND06N ND06N ND0N ND0N ND6N ND6N Cable selection chart Single core, twin insulated wires in voltage grade 00V, conforming to IS: with additional FR properties. Nominal area of conductor Sq. mm Current carrying capacity single phase In conduit Max. Resistance o per km. at 20 C Amp. Ohms Standard Colours : Red, Green, Blue, Yellow, Black. * As per IS: 96 (Part V) Above data is indicative. L&T will not be liable for damage arising from incorrect applications Chart for Star-Delta starting Colour identification of cables Motor Rating 4V, phase Full load current approx. Relay range Recommended back-up MCB 'C' Type 'D' Type hp kw amp. amp. amp. amp NC0N ND0N NC04N ND02N NC04N ND0N NC06N ND0N NC0N ND04N NC0N ND06N NC6N ND06N NC6N ND0N NC20N ND0N NC2N ND6N R phase of phase AC circuit Y phase of phase AC circuit B phase of phase AC circuit Neutral of single / phase AC circuit Earthing Derating of Wires Purpose Colour of cable 0 Ambient Temp. C 0 Rating factor red yellow blue black green

11 Cable Size Nominal Conductor Size mm² Capacities of PVC conduits Capacities of rigid steel conduits 6mm or /8" Conduit Size and Gauge 20mm or /4" 2mm or " 2mm or ¼" Number of Cables (maximum) Size of Copper Nominal cross sectional area mm² 6 Size of Conduit (mm) Number of Cables (maximum)

12 hager Board Type Enclosure Incomer Outgoing MCBs Busbar hager System designing System designing SPN Distribution Board TPN Distribution Board with SP Outgoing P N hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager test regularly : push button to trip hager hager hager hager hager hager hager R Y B N 6-way 8-way 2-way Board Type 6-way 8-way 2-way CU8N CU0N/DU0N CU4N/DU4N Enclosure CU28N/DU28N CU6N/DU6N DU42N double pole - RCCB, RCBO, MCB or isolator Incomer four-pole - RCCB, RCD - Add-on Block + MCB 6 x SP 7 Mod of pole 8 x SP 9 Mod of pole 2 x SP Mod of pole Outgoing MCBs & blanking clips Busbar 8 x SP 2 x Mod 8 Mod of pole 24 x SP 4 x Mod 24 Mod of pole 6 x SP 2 x Mod 8 Mod of pole 8 9 0

13 System designing System designing TPN Distribution Board with TP/SP Outgoing SPN Spilt Load Distribution Board hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager hager 6A AC22 BS 49 80/4 V ~ 0Hz 2 4 SB299 0N 0N test regularly : push button to trip R Y B N P N hager hager hager ION 0OFF Board Type 6-way 8-way 2-way Enclosure CU4N/DU4N - row 4 Mod Enclosure Incomer Outgoing MCBs & blanking clips CU28N/DU28N 4 pole - RCCB, RCD - Addon Block + MCB 6 x TP 6 x Mod CU6N/DU6N 8 x TP 8 x Mod DU42N 2 x SP 6 x Mod Incoming devices Outgoing devices Connection Main incomer - SF 29G - 2 pole change over switch Sub incomer - 2 pole RCCB (for high risk circuits) SP MCBs - 9 Nos. SP Busbar - 9 Mod. Busbar 2 Mod of pole 24 Mod of pole 9 Mod of pole End caps 4 x pole 4xpole 6xpole np

14 System designing - TPN DBs - PPI DBs TPN Distribution Board with per phase isolation having RCCBs in each Outgoing Phase hager hager hager hager hager hager hager hager hager hager hager test regularly : pushbuttontotrip hager hager hager hager hager hager hager hager hager hager hager test regularly : pushbuttontotrip hager hager hager hager hager hager hager hager hager hager hager test regularly : pushbuttontotrip hager 6A AC22 BS 49 80/4 V ~ 0Hz 7 SB N 0N 0N 0N N Y B R Enclosure DU6N - row 6 Mod * Incoming devices Main incomer - 4 pole Isolator Sub incomer - 2 pole RCCB in each phase Outgoing devices SP MCBs - 2 Nos. per phase Connection SP Busbar - Mod. per phase Neutral bar - per phase. * Above arrangement available with MCCB as incomer in a separate Distribution Board as standard. 22 First Aid in case of Electric Shock Which factors cause an electric shock? Contact with high-tension wires is often fatal. The upon intensity of a shock depends Voltage The Type of Current, Length of Exposure Time The Path it Takes Through the Body (the heart or head are the most dangerous routes) What can happen if you get an electric shock? Heart Failure ("cardiac arrest") Burns Nerve, Muscle, and Organ Damage What should you do if someone gets shock? To treat a person who has sustained electrical injury: Unplug the appliance and/or turn off the MCB (at the fuse box). (Merely turning the switch off will not necessarily stop the flow of current.) Call an ambulance. If the victim is not breathing, immediately begin mouth-to-mouth resuscitation. To prevent shock, Place the victim's feet higher than the head by about a foot. Cover person with a blanket or coat if available. 2 np 0 0 0

15 Check for indications of shock: Cold, Moist Skin Fast Heartbeat Paleness Feeling Faint Check for burns, which may not be visible from the outside. Sites to inspect in particular are: The fingers and toes Skin touching against metal accessories like jewelry or a belt buckle Take off any clothing over the burn - but only if it comes away without pulling skin along with it. As long as the skin is unbroken, you can rinse the burn in cool, running water to ease pain. Cover any surface burns with a sterile dressing or clean cloth. Separate burnt fingers or toes with the dressing. Take the victim to the emergency roomeven if the person is breathing, is conscious, and insists that s/he is all right. Things to avoid: Do not touch the person with your bare hands before you are certain there is no live electricity. WARNING: Never move the person if they are touching a power line or other source of high voltage. Under such circumstances keep a distance of at least 20 feet. The above precautions are for your own safety. 24 CAUTION: For the safety of the victim, do not move him/her if spinal injury is possible from an explosion or fall associated with the accident. Do not remove clothing that is stuck to the wound. Never put ice on a burn. Do not apply ointments or grease to burned skin (as with burns from flames). Do not bandage with a towel, blanket, or cotton dressing that will stick to the wound. (Instead, use a sheet for large area.) Take care not to break any blisters that have formed. Shield the burned area from chafing. What should you do if not sure if the power is off? If turning off the electricity is impossible or you can't tell whether it is off (unless it is high-voltage current), then to approach the victim: Stand on a mat (preferably rubber, but piled up newspapers/magazines could be used if necessary), and Extend a wooden or cloth object, such as a Broom handle, Chair, Piece of clothing, or Rope Sources: U.S. Centers for Disease Control and Prevention, U.S. National Library of Medicine 2

16 Important Telephone Nos.