Unless otherwise requested The time read on the timer is that required to close the left contacts. the IAC59A is set at the factory to close its right contacts at of tap value and the IAC59B is set to close its left contacts at 110% of tap value.
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GENERAL ELECTRIC COMPANY POWER SYSTEMS MANAGEMENT BUSINESS DEPT. PHILADELPHIA, PA. 19142 GENERAL ELECTRIC 7-8 0 2-6 8...
TIME-OVERCURRENT RELAYS TYPE lAC INTRODUCTION & Contact Instantaneous AC Trip Induction Outline Internal Type Circuits Unit Unit Unit Panel Drilling Connection Fig. IAC51A(-)A Fig. Fig. Fig. IAC51B(-)A Fig. Fig. IAC51R(-)A Fig. Fig . IAC52A(-)A Fig. Fig. IAC52B(-)A The Type lAC relays comprise a gro u p of relays permits instantaneous tripping for extremely high that are employed to protect against overcurrent on currents, or an induction unit with an a-c tripping...
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Time Overcurrent Relays Type lAC GEH-1753 • • • § � � •• ·- G> •• ·- G> ·- .Ill I l I I 1D �o so 7o ao eo .I .I .7 .I .8 1 MULTlPLES OF RELAY TAP SETTING Fig.2.
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Time Overcurrent Relays Type lAC GEH-1753 BURDENS The current-closing rating of the contacts is amperes for voltages not exceeding volts. current-carrying ratings are affected by the Burdens for the standard coils are given in the selection of the tap on the target and seal-in coil following table.
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. . . r : GEH-1753 Time Overcurrent Relays Type lAC A-C BUS DEVICE FUNCTION NUMBERS FOR USE WITH ALL EXTERNAL DIAGRAMS ll=1 Instantaneous Unit 1�1 Overcurrent, Relay, Type lAC 51N - Ground Overcurrent Relay, Type lAC Power Circuit Breaker Seal-in Unit, with Target (K-6375667-2) Fig.
Time Overcurrent Relays Type lAC GEH-1753 INSTANTANEOUS UNIT INTRODUCTION mounted beside the adjustable pole piece. Time current characteristics shown Fig. The instantaneous unit is a small instantaneous hinge-type unit which may be mounted on the right RATINGS front side the induction unit (See Fig. contacts are normally connected in parallel with...
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GEH-1753 Time Overcurrent Relays Type lAC TRIPPING UN I1 INTRODUCTION The a-c tripping unit is a Type REA relay unit designed to energize a circuit breaker trip coil from I&SI BREAKER TRIP COIL its associated current transformer upon the operation of the main unit of the lAC relay.
Time Overcurrent Relays Type IAC GEH-1753 APPLICATION which has contacts rated 200 amperes, can be used in conjunction with lAC overcurrent relays. The a-c tripping unit is used in Type lAC relays REAllB is not mounted inside the lAC case. where a reliable direct-current tripping source is not available and it is necessary to trip the breaker BURDENS...
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GEH-1753 Time Overcurrent Relays Type lAC INDUCTION Ut-<:-:- SEAL-IN A-C \RIP � UNIT INSTANT. Fig. 13 (K-6209294-3} Internal Connections for the Type IAC51R Relay (Front View} INDUCTION UNIT SEAL- IN UNIT SHORT FINGER (K-6209662 Fig. 14 [5]) Internal Connections for the Type IAC52A Relay (Front View)
Time Overcurrent Relays Type GEH-1753 TO TIM[!? 'STOP" TO INDICATING LIGHT WHEN CHECKING PICKUP OF MAIN UNIT TO INDICATING LIGHT WHEt INSTANT, CHECK lNG PICKUP OF INSTANTANEOUS UN IT UNIT r-- - INDUCTION UN IT X LA13 TEST PLUG INSTANT, VARIABLE RESISTOR UN IT TO TIMER...
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GEH-1753 Time Overcurrent Relays Type lAC ADJUSTMENTS TARGET AND SEAL-IN UNIT The primary adjustment for the time of opera tion the unit is made by means of the time dial. For trip coils operating on currents ranging However, further adjustment is obtained by moving from 0.2 up to 2.0 amperes at the minimum control the permanent magnet along its supporting shelf;...
Time Overcurrent Relays Type lAC GEH-1753 CONTACT ADJUSTMENT CONTACT ADJUSTMENT With the unit de-energized, the movable contact The contact s should have approximately 1/32 should lie against the stationary contact with enough inch wipe. That is the stationary contact should be tension to always insure a good closed circuit.
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GEH-175 3 Time Overcurrent Relays Type lAC CONTACT CLEANING and deterioration of the contacts. Abrasive paper or cloth leave minute particles of insulating cleaning fine silver contacts, a flexible abrasive material in the contacts and thus prevent burnishing tool should be used, This consists of a closing.
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Time Overcurrent Relays Type lAC GEH-1753 SEMi-FLUSH--PANEl LOCATION SURFACE t.ITC. WTG. STUD STUD NUIIBER NUt.IBU I <RQMT VIEW FRONT VIEW FIG. -A F IC. IAC51R IAC528 VIEW SHOWING ASSEMBLY OF WTC. HARDWARE FOR SURFACE ON STEEL PANELS. OUTLINE � DRILl DRILL 5 HOLE 5 HOLES...
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GE Power Management 215 Anderson Avenue Markham, Ontario Canada L6E 1 83 Tel: (905) 294-6222 Fax: (905) 201-2098 www.ge.com/indsys/pm...