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Standards. IS 13947 IEC 60947. Below or Equal to 1000V for AC & 1200V for DC. LOW VOLTAGE. SWITCHGEAR. SWITCHING. PROTECTION. N. Y. CONTACTOR. N. Y. RELAY. Y. Y. STARTER. SWITCH / SD. Y. N. HRC FUSE. N. Y. SFU/FSU/SDF. Y. Y. ACB. Y. Y. MCCB. Y. Y. MPCB. Y.
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Standards • IS 13947 • IEC 60947 • Below or Equal to • 1000V for AC • & • 1200V for DC LOW VOLTAGE
SWITCHGEAR SWITCHING PROTECTION N Y CONTACTOR N Y RELAY Y Y STARTER SWITCH / SD Y N HRC FUSE N Y SFU/FSU/SDF Y Y ACB Y Y MCCB Y Y MPCB Y Y
CONTACTOR As per IS 13947 PART 4 A mechanical switching device having only one position of rest operated otherwise than by hand, capable of making, carrying and breaking currents under normal circuit condition including operating overload condition.
CONTACTOR A SIMPLE ELECTROMAGNETIC SWITCH FOR FREQUENT OPERATION WITH NO - VOLT PROTECTION Core competency • High Operational Life
CONTACTOR MAIN APPLICATION AREAS • SWITCHING OF MOTORS • SWITCHING OF LIGHTING LOADS • SWITCHING OF HEATING LOADS • SWITCHING OF CAPACITORS • SWITCHING OF DC LOADS
1/L1 3/L2 5/L3 2/T1 4/T2 6/T3 SYMBOLS FOR CONTACTOR MAIN CIRCUIT
A1 A2 13 14 21 22 SYMBOLS FOR CONTACTOR AUXILIARY CIRCUIT
LIMITS OF OPERATION Pick Up – 85% to 110% of Uc Drop Off – 75% to 20% of Uc ( for a.c.) 75% to 10% of Uc (for d.c.) Where Range is specified 75% & 85% shall apply to Lower Value 110%, 20% & 10% shall apply to Higher Value
WHY CONTACTOR ? • HIGH OPERATIONAL LIFE • HIGH FREQUENCY OF OPERATION • CAN BE OPERATED FROM REMOTE • CAN BE USED FOR AUTOMATIC SWITCHING OPERATIONS • CAN OFFER NO VOLT PROTECTION
SELECTION OF CONTACTOR PARAMETERS • RATED OPERATIONAL VOLTAGE, Ue • RATED OPERATIONAL CURRENT, Ie • FREE AIR OR ENCLOSED THERMAL CURRENT, Ith & Ithe • UTILIZATION CATEGORY • ELECTRICAL & MECHANICAL LIFE
SELECTION OF CONTACTOR PARAMETERS • RATED CONDITIONAL S/C CURRENT • FREQUENCY OF OPERATION • COIL VOLTAGES • NUMBER OF AUXILIARY CONTACTS • DIMENSIONS • TERMINAL SIZE • EASE OF MAINTENENCE • AVAILABILITY OF SPARES
NON-INDUCTIVE / SLIGHTLY INDUCTIVE LOADS,RESISTANCE FURNACES AC 1 AC 2 SLIP RING MOTORS: STARTING , SWITCHING OFF AC 3 SQUIRREL CAGE MOTORS : STARTING, SWITCHING OFF DURING RUNNING AC 4 SQUIRREL CAGE MOTORS : STARTING, PLUGGING & INCHING SELECTION OF CONTACTOR UTILISATION CATEGORIES
SWITCHING OF ELECTRIC DISCHARGE LAMP CONTROLS AC 5a AC 5b SWITCHING OF INCANDESCENT LAMPS AC 6a SWITCHING OF TRANSFORMERS AC 6b SWITCHING OF CAPACITOR BANKS SELECTION PARAMETERS UTILISATION CATEGORIES
VERIFICATION OF NUMBER OF ON LOAD OPERATINAL PERFORMANCE
NO. OF OPERATING CYCLES OPERATING CURRENT IN AMPERES SELECTION PARAMETERS ELECTRICAL DURABILITY A TYPICAL ELECTRICAL LIFE CURVE FORUTILISATION CATEGORY AC4
A N = A C 1 1 + 100 B N = ELECTRICAL LIFE IN MIXED DUTY A = ELECTRICAL LIFE IN AC 3 DUTY B = ELECTRICAL LIFE IN AC4 DUTY C = PERCENTAGE OF AC 4 OPERATION OF TOTAL OPERATION SELECTION PARAMETERS ELECTRICAL LIFE IN MIXED DUTY APPLICATION WHERE,
RELAY • A device designed to produce sudden predetermined changes in one or more electrical output circuit when certain condition are fulfilled in electrical input circuit controlling the device.
BIMETAL OVERLOAD RELAY ADVANTAGES : 1. THERMAL MEMORY 2. ACCURATE PROTECTION 3. ADJUSTIBILITY 4. AMBIENT COMPENSATION 5. COMPACT CONSTRUCTION 6. LONG LIFE 7. ECONOMICAL
BIMETALLIC OVERLOAD RELAY WITH DOUBLE SLIDE MECHANISM BIMETAL UPPER SLIDE LEVER STOPPER LOWER SLIDE
KW * 1000 I FULL LOAD = 3 * LINE VOLTAGE * COS SELECTION OF BIMETAL OVERLOAD RELAYS 1 . FIND OUT THE NAME PLATE CURRENT OF MOTOR OR CALCULATE THE FULL LOAD CURRENT 2 . SELECT SUITABLE RELAY RANGE ( ENSURE THAT FULL LOAD CURRENT OF THE MOTOR IS TOWARDS THE MAX. RANGE OF RELAY) 3. ENSURE THAT RELAY TRIP CURVE IS BELOW THE MOTOR WITH STAND CURVE ( IF AVAILABLE )
SETTING OF BIMETAL OVERLOAD RELAYS 1 . FIND OUT THE NAME PLATE CURRENT OF MOTOR 2 . MEASURE THE ACTUAL CURRENT DRAWN BY THE MOTOR. 3. SET THE RELAY AS PER THE ACTUAL CURRENT DRAWN BY THE MOTOR. ( IF THE ACTUAL CURRENT DRAWN IS MORE THAN THE NAME PLATE CURRENT, INVESTIGATE THE CAUSE FOR OVERLOADING ) 4. IN CASE OF STAR - DELTA STARTER, CHECK UP WHETHER RELAY IS IN LINE OR PHASE CIRCUIT.
SELECTION AND SETTING OF BIMETAL OVERLOAD RELAYS ( FOR MOTORS WITH LONG STARTING TIME) IF THE STARTING TIME OF THE MOTOR IS MORE THAN THE RELAY TRIP TIME AT STEADY STATE STARTING CURRENT, 1. SELECT A RELAY WITH DELAYED TRIPPING CHARACTERISTICS & ENSURE THAT RELAY TRIP TIME AT STEADY STATE STARTING CURRENT IS MORE THAN THE STARTING TIME OF THE MOTOR. 2. SET THE RELAY AS PER THE ACTUAL CURRENT DRAWN BY THE MOTOR NOTE : IN CASE OF MOTOR STARTING TIME BEING MORE THAN THE TRIPPING TIME OF THE RELAY EVEN FOR RELAY WITH DELAYED TRIPPING CHARECTERISTICS AT STARTING CURRENT , BY PASS THE RELAY DURING STARTING.
WHAT IS A MOTOR STARTER ? IT IS A COMBINATION UNIT OF CONTACTOR (S) AND A RELAY USED FOR SWITCHING AND OVERLOAD PROTECTION OF THE MOTOR.
HRC FUSEMAIN APPLICATION AREAS • AS A S.C.P.D. IN MOTOR STARTER FEEDERS • PROTECTION OF LIGHTING & HEATING CIRCUITS • PROTECTION OF TRANSFORMERS • PROTECTION OF CABLES • BACK-UP TO CBs WHERE FAULT LEVEL EXCEEDS BREAKING CAPACITY OF THE CB • PROTECTION OF SMALL LOADS ON CIRCUITS HAVING HIGH FAULT LEVELS
CUT SECTION OF HRC FUSE CONTACT POP UP INDICATOR HIGH RESISTANCE WIRE BODY QUARTZ SAND FUSE ELEMENT
WHY HRC FUSE ? • EXTREMELY HIGH BREAKING CAPACITY OF UP TO 100KA • VERY FAST OPERATION IN THE EVENT OF HEAVY S/C (CAN INTERRUPT EVEN IN < 5 mSEC) • CURRENT LIMITING DEVICE - LIMITS S/C CURRENT TO A VALUE LESS THAN PROSPECTIVE PEAK - VERY LOW LET THRU’ ENERGY • NO MAINTENANCE REQUIRED • VERY SMALL/COMPACT SIZE • RELATIVELY LOW COST
SIZE In MAXIMUM PERMISSIBLE (A) POWER DISSIPATION (W) 00 100/160 7.5/12 0 160 16 1 250 23 2 400 34 3 630 48 4 1000 90 SELECTION PARAMETERS RATED POWER DISSIPATION AS PER IS 13703/PART 2 FOR gG FUSE LINK
SELECTION PARAMETERS CO-ORDINATION WITH STARTER • TYPE 1 CO - ORDINATION • REQUIRES THAT, UNDER SHORT-CIRCUIT CONDITIONS, THE CONTACTOR OR STARTER SHALL CAUSE NO DANGER TO PERSONS OR INSTALATION AND MAY NOT BE SUITABLE FOR FURTHER SERVICE WITHOUT REPAIR AND REPLACEMENT OF PARTS • TYPE 2 CO - ORDINATION • REQUIRES THAT, UNDER SHORT SHORT-CIRCUIT CONDITIONS, THE CONTACTOR OR STARTER SHALL CAUSE NO DANGER TO PERSONS OR INSTALLATIION AND SHALL BE SUITABLE FOR FURTHER USE. THE RISK OF CONTACT WELDING IS RECOGNIZED, IN WHICH CASE THE MANUFACTURER SHALL INDICATE THE MEASURES TO BE TAKEN AS REGARDS THE MAINTENANCE OF THE EQUIPMENT
RELAY FUSE CONTACTOR CH. CH. BR. CAPACITY CROSS-OVER POINT MOTOR CURRENT TIME (SEC) 1 2 3 4 5 6 7 8 9 10 CURRENT (n IrM) SELECTION OF HRC FUSE TYPE 2 COORDINATION
RATED VOLTAGE • RATED CURRENT • RATED BREAKING CAPACITY • TYPE • SIZE • TIME-CURRENT CHARACTERISTICS • COORDINATION WITH STARTER • RATED POWER DISSIPATION • DISCRIMINATION WITH OTHER SCPDs SELECTION OF HRC FUSE PARAMETERS
SWITCHES, DISCONNECTORS, SWITCH DISCONNECTOR & FUSE COMBINATION UNIT AS PER IS 13947 (PART 3)
SWITCH A MECHANICAL SWITCHING DEVICE CAPABLE OF MAKING , CARRYING AND BREAKING CURRENTS UNDER NORMAL CONDITIONS WHICH MAY INCLUDE SPECIFIED OPERATING OVERLOAD CONDITIONS. SHALL BE ABLE TO CARRY FOR A SPECIFIED TIME CURRENTS UNDER SPECIFIED ABNORMAL CONDITIONS SUCH AS THOSE OF SHORT CIRCUIT.
WHY S/W-DISCONNECTOR ? • FOR ISOLATING THE MOTOR FEEDER FOR ANY MAINTENANCE WORK • CAN BE USED AS BACK-UP SWITCHING DEVICE IN CASE OF EMERGENCIES (LIKE CONTACTOR WELDING) • POSITIVE OPENING OF MAIN CONTACTS • ADDITIONAL FACILITIES LIKE DOOR INTERLOCK & PADLOCKING
EQUIPMENT DEFINITION FUNCTION MAKE - CARRY - BRAEAK ISOLATION & CARRY MAKE-CARRY- BREAK CURRENT & ISOLATION SWITCH DISCONNECTOR SWITCH - DISCONNECTOR SWITCH - DISCONNECTOR - SWITCH FUSE FUSE DISCONNECTOR - FUSE • FUSE - SWITCH FUSE - DISCONNECTOR FUSE - SWITCH - • DISCONNECTOR
FREQUENT INFREQUENT TYPICAL OPERATION OPERATION APPLICATION UTILIZATION CATEGORY AC20 A AC 20 B CONNECTING & DIS- CONNECTING UNDER NOLOAD CONDITIONS AC 21 A AC 21 B SWITCHING OF RESITIVE LOADS INCLUDING MODERATE OVERLOADS AC 22 A AC 22 B SWITCHING OF MIXED RESISTIVE & INDUCTIVE LOADS , INCLUDING MODERATE OVERLOADS AC 23 A AC 23 B SWITCHING OF MOTOR OR HIGHLY INDUCTIVE LOADS
ADVANTAGES : • FUSELESS PROTECTION SYSTEMS WITH LOW DOWN TIME • INTEGRATED COMPREHENSIVE PROTECTION • LOWER LET THROUGH ENERGY • COMPACT • AVAILABILITY OF VARIOUS ACCESSORIES • HIGH ELECTRICAL LIFE • HIGH BREAKING CAPACITY • EASE OF CO-ORDINATION
AUX. CONTACTS * INDICATE ---- ON / OFF POSITION ---- TRIP same as OFF TRIP INDICATING AUX. CONTACTS *S/C signaling contacts *O/L signaling contacts SHUNT RELEASE ----- REMOTE TRIPPING UNDER VOLTAGE RELEASE DOOR COUPLING HANDLE Accessories with MPCB
CROSS OVER POINT ( IN BUILT ) MPCB Type 2 co-ordination Application : Stand alone device determination of cross over point T I M E MOTOR CURRENT 5-6In 14In CURRENT
MPCB SCHEME 1 SCHEME IS RECOMMENDED WHEN SWITCHING OF MOTOR IS INFREQUENT MPCB PROVIDES : * PROTECTION AGAINST SHORT CIRCUIT * PROTECTION AGAINST OVER LOAD + S/P * SWITCHING OF MOTOR MPCB I> MOTOR M
MPCB SCHEME 2 SCHEME IS RECOMMENDED WHEN SWITCHING OF MOTOR IS FREQUENT MPCB PROVIDES : * PROTECTION AGAINST SHORT CIRCUIT * PROTECTION AGAINST OVER LOAD + S/P CONTACTOR IS USED FOR *SWITCHING OF MOTOR UNDER NORMAL CONDITION MPCB I> CONTACTOR MOTOR M
MPCB SCHEME 3 MPCB PROVIDES : * PROTECTION AGAINST SHORT CIRCUIT O/L RELAY PROVIDES : * PROTECTION AGAINST OVER LOAD + S/P CONTACTOR IS USED FOR * SWITCHING OF MOTOR UNDER NORMAL CONDITION * SWITCH OFF MOTOR ON TRIP COMMAND FROM RELAY OUTPUT MPCB I> O/L RELAY CONTACTOR MOTOR M