Snowmelting controldevice

I have electric heating cables, to melt the snow on my doorsteps. Today, these are controlled by a normal power regulator, but I would like to control them from Smartthings. Does anyone have a suggestion for a Z-Wave or Zigbee device that can controll these cables? I have found several thermostats, but that will not work, as I do not have a temperature sensor mounted with the cables.