BS-519 › Complete Document History
Specification for tractive armature direct current neutral-polar line relays for railway signalling


Obsolete Revision Information:
   WITHDRAWN - NO REPLACEMENT - July 7, 2014
   PD 4017 - AMENDMENT 2 - Jan. 1, 1961
   PD 2283 - AMENDMENT 1 - Sept. 1, 1955
   1950 EDITION - REAFFIRMED IN 1980 - July 14, 1950