INSULATION TEST EQUIPMENT FOR LOCAL CROSSBAR SYSTEMS 633 



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 0.8 



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2 34568 10^ 2 3 



insulation resistance in ohms 

 Fig. 3 — Wet weather tests — reconditioned Outside Plant. 



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insulation of one or more pairs near the break absorbs the moisture and 

 the insulation resistance of the affected pairs is lowered. Tests made from 

 about 3 A.M. to 5 A.M. are effective in detecting these leaks and by 

 applying the latest fault locating methods, many of the sheath breaks 

 can be located. The test equipment is so arranged that, for the most 

 part, lower leak conditions on the line which may be present outside 

 of the aerial cable will not register on these tests for cable defects. 



BENEFITS DERIVED FROM RAPID LINE-INSULATION TESTING 



With the aid of rapid line-insulation test equipment the maintenance 

 personnel can correct the greater part of insulation defects on a pre- 

 ventive maintenance basis which results in a reduction of subscriber 

 reports. Service to the customer is thereby improved, maintenance effort 

 is reduced and repairs on an emergency basis often involving the ex- 

 penditure of overtime are required less frequently. Rapid line-insulation 

 testing is also of great value in rapidly determining the extent of storm 

 or flood damage and makes it possible to direct immediate efforts where 

 the greatest benefits will be derived. 



