Question regarding electricity (amperage) on my first grow, help please!

I'm currently planning my first medical grow (600w), but have some questions regarding the amperage in my "grow room". The grow would be situated in my bedroom (15 amp circuit on a 125 amp breaker ), the current amp usage in this room is around 5.5, but could spike up to around 6.5 when my pc is at max load. The fan I plan to use is a 6" vortex @ 66 watts, so between the light and fan the grow would be pulling 5.55 amps. From what I understand the ballast itself will add to that value, but I can't get a wattage on the ballast (http://www.amazon.com/gp/product/B00B5HZOSK/ref=ox_sc_act_title_8ie=UTF8&psc=1&smid=A3VTE9RTFS7WGL).

Excluding the ballast and any other fans that I put in the tent for air circulation, that's 11 amps potentially 12 which puts the circuit at 80%. This is a pretty new building with all new wiring, and I'm wondering what the dangers are of running 13-14 amps on a 15 amp circuit. My amperage also seems to spike when things are first powered on (TV, PC, Lamps, Fans, TV causing the biggest spike). I'm guessing that running a 600w grow in this room probably isn't a good idea, but I'm assuming I would be safe @ 400? Any help would be appreciated.

Also I believe the breaker is rated at 100%, it's a General Electric Breaker model number is TLM2012C, but can't find much info about it. Not sure if this makes a difference.

i wouldn't run over 80% for more than an hour or 2 (12A). definitely not 13 or 14A for more than a few minutes.

can you run a thick extension cord from another circuit into the bedroom for your tv and computer? try to keep just the grow stuff on the bedroom circuit.

or if you own the place, hire an electrician to add another circuit in the bedroom.

inthis lawsuit happy society, everybody and their uncle will sue the shit out of you for negligence if there is a fire.

Yeah I'll probably have to run an extension cord from an adjacent room or drop the grow down to 400w in which case I don't think I'll ever go past 11A. Thanks for the input.

no prob. just something to think about: you get double the lumens with the 600 vs 400 for only 200 more watts.

Well I don't own the place, so adding another breaker is out of the question, and running an extension cord is also impractical, because no heavy duty cord is going to fit under these doors and I can't go punching holes in the walls. 400w will be plenty for 4-5 autoflowers, yields won't be as high, but I won't burn the place down (I hope).

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