Westinghouse DB-100, Instructions Manual

Page 1: ...s Current Rating DB 75 DB 100 4 000 Amperes 5 000 Amperes D C 6 000 Amperes Only 2 000 Amperes 2 500 Amperes 3 000 Amperes Westinghouse Electric Corporation Switchgear Division East Pittsburgh Pa I B 33 850 4 5D Effective November 1966 Supersedes I B 33 850 4 5C May 1962 Courtesy of NationalSwitchgear com ...

Page 2: ...tment of Trip Screw Operation Standard Overcurrent Tripping Device Selective Overcurrent Tripping Device Instantaneous Overcurrent Tripping Device Single Element Time Current Characteristics Calibration MaintenanceX Control Relay Inspection Maintenance Shunt Trip Attachment Inspection Maintenance Undervoltage Trip Attachment Undervoltage Time Delay Attachment Inspection Maintenance Auxiliary Switc...

Page 3: ...spection Maintenance Key Interlock Attachment Inspection Maintenance Rectifier Unit for A C Undervoltage and A C Electric Lockout Attachments Inspection Maintenance Reverse Current Trip Attachment Inspection Maintenance Field Discharge Switch Recommended Spare Parts 26 26 29 29 29 29 29 29 30 30 30 30 30 30 30 30 30 31 S 33 V 34 v T 1 3 Courtesy of NationalSwitchgear com ...

Page 4: ... 9 Schematic and Typical Time Current Characteristics of Overcurrent Trip ping Device with Long Delay and Short Delay Elements 10A Schematic Diagram of Overcurrent Tripping Device with Instantaneous Element Only 10B Typical Time Current Characteristics of Overcurrent Tripping Device with Instantaneous Element Only 11 Control Relay Construction Details 12 Shunt Trip Attachment Construction Details ...

Page 5: ...the breaker should be mounted in an enclosure suitable to local operating conditions A selection of standard enclosures is available for various applications Important To assure proper functioning inspect each breaker at reg ulai intervals in accordance with a systematic maintenance schedule The frequency and character of the inspections will for the most part be determined by the severity of the ...

Page 6: ...s lifeisa PSlPfp S A slim mM yii ip M 1 v i t t Vv2 iii 11 ii assse f V 1 Ifflt m rnmt P f r i iutV S I 3 v jy I A Siii RP r v v x mm i I V 1 W r mil 1 h 5 1 fc i i 1 f V _ V i i 6 Courtesy of NationalSwitchgear com ...

Page 7: ...le No 1 NET WEIGHTS OF 3 POLE BREAKER DB 75 475 lbs Add 50 lbs for D O DB 100 525 lbs Add 75 lbs for D O DBF 40 550 lbs Add 75 lbs for D O Immediately upon receipt examine shipment for any loss or damage incurred during shipment If injury or rough handling is evident file a damage claim at once with the transportation company and notify the nearest Westinghouse Sales Office When unpacking be sure ...

Page 8: ... handle is supplied with each order of DB 75 and DB 100 breakers This handle is for maintenance only and in no case should it be used for closing the breaker when primary circuit is energized Typical circuit breaker wiring diagrams are shown in Fig 2 The connecting cables or bus bars should have adequate current carrying capacity or heat will be conducted to the circuit breaker resulting in possib...

Page 9: ... V l I B 33 850 4 5D INSTALLATION DB AIR CIRCUIT BREAKERS 4 v r V I 7 FIG 1 Type DB 100 Air Circuit Breaker Outline and Mounting Dimensions 9 Courtesy of NationalSwitchgear com ...

Page 10: ...I INSTALLATION 4 n i Y r i 4 3 i f t V FIG 1A Typo DB 75 Air Circuit Breaker Fixed Outline and Mounting Dimensions 10 Courtesy of NationalSwitchgear com ...

Page 11: ...t I B 33 850 4 5D INSTALLATION DB AIR CIRCUIT BREAKERS V h 4 FIG IB Type DBF 40 Fixed Outline and Mounting Dimensions ii Courtesy of NationalSwitchgear com ...

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Page 13: ...C i m K H S T f Q O o LU DC a 2 O JC z POR O BREAKER OPERATION StaueNCt 4 DEVICE LEGENO SEE PAGft l 4 O d 1 I Ti XIN X Y E J3 i SCHEMATIC PIG 1 PMUL Z DB 75 V Dft 100 A CB s J2iSX 5 EP 600J OI Fixao w tL ggaaMTwffwSTw lau ffF 1 SUB 1 o o o a o o o o BQ H W AUX ALM SW l SW 1 0 t mo 7 X r TOP h NEAREST PANEL i SOT 4 0 y 4 POLE AUX S TC i J IUV N AUX W SW TC V 7 r8OT J f raft x Q Ph fRecY UNIT FOR LO...

Page 14: ...ed te inch Maintenance of Contacts Rough or high spots should be removed with a file or sandpaper When dressing contacts be sure to protect the hinged contact of all poles with a cloth to prevent foreign matter from lodging in the hinged contact Cautions All power must be removed when replacing maintaining or adjusting contacts OPERATING MECHANISM The operating mechanism Figs 3 3A is non ad justab...

Page 15: ...1 KB 33 8S0 4 5D INSTALLATION DB AIR CIRCUIT BREAKERS t 4 v J V FIG 3 Cross Sectional View o Air Circuit Breaker 15 Courtesy of NationalSwitchgear com ...

Page 16: ... A f T r tlf w r V 2 z w Z z O M 1 M Q GO 3 a CD Cd 0 cn p 3 a tJ w o o 3 CD CD 3 O CO O 3 O 3 CD P 3 Q S CD Q tr p 3 M 0 3 ...

Page 17: ...llows 1 Caution Remove the close coil circuit voltage 2 Disconnect the wires from the close coil ter minals 3 Loosen the locking clip 4 on the bottom of the moving core RECOMMENDED CLOSING FUSE AMPERE RATING FUSE CLOSING COIL 7 BURDEN1 NOMINAL CONTROL YOLTAGE STYLE NUMBER CLOSING AMPERES TRIPPING AMPERES BREAKER 600 VOLT 250 VOLT TYPE Standard Tima Tima Standard NEC Lag NEC Lag All 48 DC 125 DC 25...

Page 18: ...ve bolts 3 and using a rawhide or plastic mallet remove the bottom stationary core 7 6 Remove the coil 7 After assembling coil and breaker but before connecting the coil ch k proper co ordination between breaker closing ahd relay tripping Ener gize relay operating coil only Fig 11 and manual ly close breaker very slowly The relay contacts should trip free slightly before the position at which the ...

Page 19: ...he breaker Then loosen the two bolts at the top of the mounting frame while supporting the trip unit so that it does not fall These two bolts clamp a slotted angle mounting bracket and merely have to be loosened they do not have to be removed from the mounting frame The trip unit is then free to be removed from the breaker by lowering it down behind the breaker platform To install a tripping devic...

Page 20: ... alone will not trip the breaker Operation Standard Overourrent Tripping Device Ke er to Fig 7A When a small overload current flows through the breaker pole unit conductor R it causes the moving o 1 J v I f LEGEND A LONG DELAY STATIONARY MAGNET 8 LONG DELAY MOVING MAGNET C LONG DELAY FORCE LIMITING SPRING D DIAPHRAGM E AIR CHAMBER F LONG DELAY VALVE AND DIAL G LONG OELAY PICK UP CALIBRATION SPRING...

Page 21: ...n spring C which is restrained by diaphragm D until sufficient air has entered valve P to permit the spring assembly C to lift crank J and trip the breaker by rotating the trip finger K A discriminator arm is used on the selective over current trip units to make the unit behave as an overcurrent tripping device However the selective instantaneous type trip unit while the breaker is overcurrent tri...

Page 22: ... achieved by chang ing the spring force applied to the smaller instan taneous armature The flat portion of the curve at the bottom repre sents the minimum time for the breaker to clear when fault currents exceed ten times the trip unit rating bracket and the trip crank When this latch is engaged the short delay armature will lift the trip crank directly if the current is greater than the short del...

Page 23: ...rrent Tripping Device with Long Delay and Short Delay Elements definite procedure and technique as well as spe cialized equipment Because few customers have access to such equipment it is highly recommended that trip units be returned to the factory if it appears that they need to be calibrated Maintenance In ordinary use this trip unit needs very little maintenance Any accumulation of dust should...

Page 24: ...ore travel Slowly open the breaker and make sure the lift link and relay toggle release return freely to their normal positions Maintenance Remove screw in front cover plate Remove cover by grasping it at the bottom and pull down and out Check for loose screws especially at contacts Replace cover and check for loose mounting bolts y coil 5 i I SHUNT TRIP ATTACHMENT The shunt trip Fig 12 mounts on ...

Page 25: ...INTENANCE DB AIR CIRCUIT BREAKERS l i 71 i r RELAY RELEASE LEVER SOLENOID J LIFT LINK H i J cr v b i u RELAY TOGGLE RELEASE U U J FIG 11 Control Relay Adjustment and Construction Details 0 Courtesy of NationalSwitchgear com ...

Page 26: ...ction Hold th U V trip lever down and close the breaker manua y Release the trip lever VV fy Caution Do not use your fingers to hold and release the U V reset lever Maintenance Check for loose bolts and faulty coils AUXILIARY SWITCH The auxiliary switch Fig IS mounts on top of the platform to the left of the operating mechanism The contacts will carry IS amperes continuously or 250 amperes for 3 s...

Page 27: ...t B 33 850 4 5D MAINTENANCE MDBff AIR CIRCUIT BREAKERS A i v W FIG 13 Undervoltago Trip Attachment Construction Details v Courtesy of NationalSwitchgear com ...

Page 28: ...ttachment Construction Details y BACK COVER rEND BUSHING 1 SHAFT Ji LEVER x t Z CONTACT FINGER 1 V V 1 w rtr CONTACT ROTOR o a 1 CASE i WlUSllISl 3E FRONT COVER M e FIG 15 Auxiliary Switch Construction Details r v r 28 Courtesy of NationalSwitchgear com ...

Page 29: ...n necessary Check for loose bolts KEY LOCK ATTACHMENT For Fixed Breakers The key lock Fig 18 mounts on the right side of the operating mechanism frame The key can be removed in the open or closed position of the breaker Inspection Push the trip button and turn key to the locked position The key is then removable and the breaker is locked in the trip free position Replace key and rotate to the unlo...

Page 30: ...rcuits The first is the potential coil which magnetizes the armature and the second is the main current which magnetizes the frame When current flows in the forward direction arma ture movement is prevented by a stop When the current reverses the armature rotates in the opposite direction and trips the breaker After tripping the reverse current armature is reset by opening the potential coil circu...

Page 31: ... n 5 tfrsr SCHEMATIC I 1 3 I I I i u u il I 3 I 1 tel J 7 TERMINAL BLOCK zTRANSFORMER FIO 19 Rectifier Unit for A C Electrical Lookout Attachments ward pole An audible click should be heard from the switch before armature reaches stop posi tion Adjustment can be made at lower trip screw Maintenance Check for loose bolts of attach ment as well as bolting of associated connectors Check potential coi...

Page 32: ...ATURE CD T I POTENTIAL COIL i i i i I r I I i i l 1 i g i 3 0 H3S i j Q MICRO SWITCH CALIBRATION PLATE FIG 20 Reverse Current Trip Attachment Types DB 75 and DB 100 Air Circuit Breakers I v v I V a 32 Courtesy of NationalSwitchgear com ...

Page 33: ...he contacts if necessary check contact relationship and adjust if necessary Check for loose bolts riELD DISCHARGE SWITCH m The DBF 40 breaker is a two pole DB 100 breaker having special arc chutes and modified arcing con tacts plus a field discharge switch mounted on the center pole Fig 21 The field discharge switch is normally shipped with an overlap of approximately 1 32 between the side pole co...

Page 34: ...lowout Coil and Circuit L P Blowout Coil and Circuit R P Moving Contact Stationary Contact Cover 1 2 1 1 2 l 1 2 1 1 2 1 2 4 2 1 1 POLE UNIT Stationary Arcing Contact Stationary Main Contact Top Fig 3 No 417 No 420 No 420 No 421 No 421 No 416 No 401 6 12 3 3 24 12 DB75 15 DB100 12 DB75 18 DB100 12 30 15 12 24 Stationary Main Contact Bottom 13 30 12 3 6 Moving Arcing Contact Moving Main Contact 3 3...

Page 35: ...f il i MEMORANDUM i n f Ls t f f f 7 V i 35 Courtesy of NationalSwitchgear com ...

Page 36: ... w hr i I s Printed in U S A Courtesy of NationalSwitchgear com ...

Page 37: ...e r Whan ordering optional attachment r specify Crtolce of Specification item ShuntTrip Attachment Specify oonwal voltage do or c and frequency Manually Operated Breaker k UndorvoUage Trip Insaantanaous ortime delay specify control voltage dc or ac and frequency U Non Arfjusiabfe Manually cr electrically reset specify number of contacts If trlcally reset specify control voltage dc or ac and freque...

Page 38: ...e for AB Types 115 AC 250 DC 230 AC 24 DC 48 DC 125 DC Control Voltage v 2 1 3 0 1 5 Close Current SR Amp Shunt Trip Currant Amp Spring Charge Motor Amp 3 5 0 2 0 L O NA 2 0 1 0 2 0 1 0 5S 6 0 1 5 t 5 3 0 3 0 NA 7 5 190 250 190 250 95 125 95 125 90 130 70 140 180 260 14 280 40 50 28 60 Close Voltage Range Trip Voltage Range 1 Not rcoommended voltage 2 Chec WastlngJiause for application at this con...