What I am going to be running this year is 2 P12r's and each one will have 2 Mean Well Se-350-12. I will be running 12 half strings of these lights from Ray http://www.aliexpress.com/store/product/5m-led-digital-strip-DC12V-input-WS2811IC-256-scale-10pcs-IC-and-30pcs-5050-SMD-RGB/701799_568458133.html from each one. My question is this, most power bars are rating for 12 to 15 Amps. Would I be overloading the power bar plugging all 4 Mean Wells into it, and then the power bar into a 20 or 30 amp plug in, or am I going to have to split them up? I am not sure how to calculate the amp draw from all of this strings. Any help would be appreciated.

to figure out the current draw (Amps) you take the Watts / volts, so a 350W 12V power supply at allow you to use 30Amps at 12V (- 20% for losses) so at 110V the current draw will be 350 / 110 = 3.18A at full load