WARNING ON TIMERS !!!!!!

Be advised that not all 15 amp rated timers (such as at Home Depot) can handle a 1000w HID. I bought an Intermatic "15 amp" timer at Home Depot. I came within seconds of burning down my house from the overheated circuit!! I brought this up to my local Brew n Grow supply store. They sold me an Intermatic timer that looked the same as the failed Home Depot one but with a different model number. They told me that Intermatic private labels the "inferior" "15 amp" timers for Home Depot but that the Home Depot timers cannot handle the "inductive loads" of a 1000w HID. I used the Brew N Grow timer and it ran as it should..no heat on plug,timer or circuit. I suspect that a growers fire in Illinois last year was caused by this situation.
BE SAFE! DO NOT BUY "15 amp" timers from Home Depot! If you DO use "15 amp" Home Depot timers use them ONLY on 400w HIDs. Buy them ONLY from grow shops in your area or from reputable suppliers on line. SAFETY is the life blood of your operation. I was sick for a week thinking about the possibilities from that Home Depot timer. I sleep well now at night.

There still my be DANGER Will Robinson!

Amperage=Watts/Volts

Inductive Load:
Electrical devices generally made of wire that are coiled to create a magnetic field to produce mechanical work when energized. Examples of inductive loads include motors, solenoids, and relays. Inductive loads exhibit inrush of current when energized that can be many times the steady state holding current. When de-energized, the magnetic field collapses, generating a high voltage transient. This transient can cause arcing across mechanical switching contacts or can cause damage to solid-state contacts.

Inrush Current:
The initial surge of current through a load when power is first applied. An important specification to consider whenever evaluating an interface. Inrush current to an inductive load (solenoid, connector, etc.) is up to ten times the holding current.

Holding Current:
1) A specification of a load, especially an electromechanical load. The current that is drawn by a load while it is energized. Also called "sealed current" of a load. See "inrush current". 2) The current necessary to maintain a thyristor in the "on" state.

So it's basically like this; if you are using 1000 watts at 120v your amperage is at 8.333. Well within the bounds for the holding current or 15 amp system. Now when you add in the factor for inrush current with the 10 multiplier you now have 83.333 amps to deal with. With safety in mind, you may want to go with a 40 amp timer at a 220 voltage. This would bring the intermittent amps down to 43 during start-up....it's still a little bit over the mark but within safe limits. Remember also, most all household receptacles are also rated for 15 amp service!

Thanks for explaining it Psycho.