Occasional checks on cali bration as well as on coordination and freedom of all moving parts, must be included in the maintenance schedule. Consult Westinghouse engineering and service personnel for recommendations pertaining to special operating or maintenance conditions.
Be sure that the contacts are clean and Net weights of Types DB-15 and DB-25 are given properly aligned. For a description of contact align in Table No. 1 below.
PART TWO INSTALLATION Type "DB" circuit breakers are furnished as com differ and should be obtained from the appropriate plete unit assemblies and the installation consists outline drawing. (1) bolting them to the supporting framework The following procedure applies to all enclosures: or structure;...
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� 4 4..!.. <t_ BKR. <t. B KR. MIN. � 7� B KR. 7E... � c:::J VIEW "s" VIEW " A " VIEW "c" CUTOUT I N DEAD FRONT DOOR OR COVER FRONT VIEW OF STUD LOCATIONS, FRO NT VIEW OF STUD LOCATIO N, CUTOUTS DRILLI NG FOR MOU NT...
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SHUNT TRIP BOT. AUX.SW. WIRING DIAGRAM (F.V.) WIRING DIAGRAM (F.V.) FIXED PANEL REV ERSE CURRENT � OPERATION SEQUENCE · 1 �-� 1 1 ---- ---- r-- -- -- -, I. CONTROL SW. CS-C CLOSED. � 2. "X" REL AY PICKS UP a SEALS IN THRU AUX. CONTACT "x": ,-FL-, 3.
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-� 12 !! 2 7 1. � -J2 ;i 17 i\ 16.L 9 08-15 FINGER CLUSTER 4i x 3jx3 DIA. TOP AND BO TTOM !"ll"l CUSTOMER ' S CABLE TWO CABLES SHOWN- WHEN SINGLE CABLE IS USED, INSERT CABLr IN 3 KN0 2 C 3 KO ��...
A small quantity of oil is placed on th�dle shaft, the roller lever roller, and the lat The DB-15 contacts are adjusted to obtain lA-inch the factory. The tripping load should not exceed horizontal travel of the cross bar after the contacts 14 ounces measured at the trip screw.
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TATIONARY ARCING CONTA CT ROLLER L E V ER OIL HOLE CLOSING S OL ENOID FIG. 6. Cross-Sectional View of Type DB-25 Circuit Breaker...
The overcurrent tripping devices of the various tripping devices of ampere ratings up to a maximum ampere ratings are of the same general construction of 225 amperes can be applied to the DB-15 circuit and size. (See Figs. 7 and 7A).
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I 00 �8 � U> 3.5 ;:: � "' � � 1.5 DB-25 DB-15 INSTANTANEOUS PICKUP (1000%) (I NT RTG. 25000 A.) (INT. RTG.I5000 A.) �- -� COIL RATINGS (AMPS.) COIL RATINGS (AMPS. ) 1 25 1 00 12 CYCLES 1 00 .
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"D B " AIR CIRCUIT BREAI4�ERS P ''""' 1000 D -YI-+ 7 ::::! 6 3:: <.) "-' � "-' CURVE A 70 AMP. LOAD BREAKER WITH LONG TIME DELAY INST TRIP CURVE C 300 AMP. BREAKER WITH LONG TIME DELAY INTERMEDIATE SHORT TIME DELAY �...
STATIONARY FRAME CORE MOVING CORE LOCATION TRIP LEVER DETAILS FIG. 10. Shunt Trip Attachment-Location and Construction Details SHUNT TRIP ATTACHMENT spring load and consequently raises the drop-out voltage. Turning the screw out lowers the drop-out shunt trip mounts on top of the platform ·...
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LOCATION DETAILS RESET LEVER SCREW TRIP BAR r ., COVER MICARTA STATIONARY CORE FIG. 1 1. Undervoltage Trip Attachment-Location and Construction Details...
UNDERVOLTAGE TIME DELAY ATTACHMENT The undervoltage air dashpot time delay attach ment mounts on the front of the undervoltage trip, replacing the moving core cover. (See Fig. 12). The needle valve screw in the top regulates the opening through which the air is forced and con sequently the time delay.
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direction of current flow in that pole is reversed. When the series coil current is flowing in the for ward direction, armature movement is prevented by a stop. When the series coil current is reversed, the armature rotates in the opposite direction to trip the breaker.
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LOCATION I I . r,===i I I i / � ADJUST FOR I STATIONARY CONTACT CROSS BAR INSULATING Ll N DETAILS . I . l�- - J FIG. 14. Field Discharge Switch-Location and Construction Details...
FIELD DISCHARGE SWITCH �aintenance. Remove power from the break er, clean the contacts if necessary, check the contact The field discharge switch is ordinarily used with gap and adjust if necessary. Check for loose bolts. a two-pole breaker, and mounts on the center mould ed pole unit base.
ALARM SWITCH ATTACHMENT Inspection. Close the breaker manually and trip by rotating the breaker handle to be sure the The alarm switch mounts above the shunt trip alarm contacts do not "make". Repeat the above attachment (see Figs. 16 and 16A) and will energize procedure except trip by raising the trip bar and the alarm circuit on all opening operations except...
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"DB" AIR CIRCUIT BREAKERS LOCAT I ON C O I L FRAM E MOVI NG CORE BRAC KET DETAI L S FIG. 17. Electric Lockout Attachment-Location and Construction Details •...
LOC K CY L I NDER LOC AT I ON FIG. 18. Key Interlock Attachment-Location and Construction Details KEY INTERLOCK ATTACHMENT position . The key is then removable and the break er handle is locked in the tripped position. Replace The key interlock mounts on the right side of the key, apply force in the counterclockwise direc...