Just got my Sense home energy monitor and was going to do the install when I realized that the space I thought I had free in my (Square D) electrical panel was actually occupied by a double wide, double pole breaker:
I had not seen these before so I did some research and found that these breakers were made by Square D back in the 60s/70s but have since been obsoleted. From what I've read, you can replace these double wide breakers with the QO style breakers which only take up one side of the panel.
Doing this will free up the space I need to install the double-pole breaker for the Sense. My question is, does anyone know if this is kosher? Note: this breaker feeds a sub-panel.