Does anyone have, or know where is located, an Instruction Leaflet or Brochure for a P&B Golds Type M3 Thermal Overload Relay? Specifically, it is a 14 minute Type M3, probably circa 1950.
I have seen some various references to typical life expectancies of electrical switchgear, including IEEE 493 and NFPA 70B. However, an earlier thread mentioned two papers which no longer link, including:
http://www.ise.nus.edu.sg/proceedings/apors2000/fullpapers/17-01-fp.htm...