Electric Eagle
I install many Square D (QO & Homeline) and Cutler-Hammer loadcenters and the tandem breakers will NOT fit in any position. You must be using the old style breakers that are for replacement use only. The QO tandem breakers have a hook on them that will only fit in designated positions and the Homeline/Cutler-Hammer BR Breakers have a clip on the end of the breakers that will only fit on notched busses. I don't use any Cutler-Hamer CH so I don't know how their CTL feature works.
Curt
