Here are three great links to check on your panel safety! FPE and Zinsco electrical panels are fire hazards and should be replaced immediately.
http://www.ismypanelsafe.com/fpe.php
http://www.ismypanelsafe.com/zinsco.php
https://inspectapedia.com/electric/Zinsco_Electrical_Panels.php
http://www.ismypanelsafe.com/fpe.php
http://www.ismypanelsafe.com/zinsco.php
https://inspectapedia.com/electric/Zinsco_Electrical_Panels.php