UL497A Secondary Protectors for Communication Circuits.pdf

UL 497A
SBN0-7629-0626-X
Secondary Protectors for
Communications Circuits
MARCH 20. 2001-UL 497A
tr1
Underwriters Laboratories Inc (UL)
333 Pfingsten Road
Northbrook. L 60062-2090
UL Standard for Safety for Secondary Protectors for Communications Circuits, UL 497A
Third Edition. Dated March 20. 2001
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