Ordinary household timers - when used alongside HID ballasts and industrial lighting equipment - are not able to withstand high inductive loads. These kinds of timers can break easily when overloaded, which could result in your strong, intense grow lights being left on permanently. Of course, this is bad news for the plants in your grow room.
But the Lumii Heavy Duty Timer is different. As the name suggests, it has been built to withstand high loads, including the inductive loads produced by high wattage ballasts. With this timer, no additional contactor is required, saving you from buying another piece of equipment.
This timer comes with 96 switching operations within a 24 hour period (every 15 minutes), and is suitable for timing 1 x 600w HID ballast or up to 6 x 200w CFLs.