My oil filled heaters pop my power strips on my Rancos when their set on high.
I can only run mine on Medium.
Therefore I have to have 2 Double Rancos running 2 oil filled heaters on medium.
Now that I think about it, my original ranco's were bought from Jeff Ronne at Boaphile, while the Johnson's were bought from Reptile Basics. I'm guessing Boaphile's powerstrips handle a little more power before tripping compared to RBI's.