How dangerous are extension cords?

[Batboy]

The best electricity option for my cab that doesn't involve new wiring/circuits/etc. (of which I know nothing and don't trust anyone), are 2 outlets in the room that are each on their own circuits and are not used.

Unfortunately the outlets are far from the cab. I would need a 25' extension cord for one outlet and a 50' cord for the other in order to have enough cord to be properly hidden around the borders.

I will be running a 400w light, fans and a speed controller -- all in all, not too much juice.

If I decided to run 2 14 gauge medium duty indoor/outdoor extension cords, how much risk am I taking?

 

[Amstel Light]

why not cough up the $ for heavier gauge if your worried?

 

[toastfighter2]

Like Amstel Light said, spend the loot on a good extension cord and you won't have to sweat it.

 

[Batboy]

ooops. I meant to say that I have 12 gague heavy indoor/outdoor. so I shouldn't sweat it?

 

[GanjaGrow]

12 gauge should be able to handle the wattage you posted just fine. I wouldn't sweat it.

 

[THCV]

educate yourself: AWG current ratings

in a nutshell, with 400w you'll be fine, with 14AWG and definitely overbuilt with 12 AWG. 400/120v=3.3Amps, not much. Add the rest and you are still probably under 10A, which is doable at 14 or 12.

 

[geopolitical]

Only issue you should also be aware of on extension cords is occasionally you can get some corrosion inside the plug under hot/humid conditions depending on build quality. Every finish of a grow I tend to inspect plugs, timers, strips, bulbs, fans. Anything that's even slightly questionable gets chucked and replaced. Nearly every item in a grow will eventually wear out. It's way cheaper to replace them before that time than it is to suffer a failure mid-grow.

 

[isit4.20yet]

educate yourself: AWG current ratings

in a nutshell, with 400w you'll be fine, with 14AWG and definitely overbuilt with 12 AWG. 4002/120v=3.3Amps, not much. Add the rest and you are still probably under 10A, which is doable at 14 or 12.

The problem with that math is it doesn't take into account inductive reactance/power factor. My 150w HPS uses 3 amps startup current before it settles down to 1-1/2 amps. A 400W HPS/MH lamp on a magnetic ballast could draw as much as 9 or 10 amps startup current for a couple minutes. That said, a 12 AWG cord is probably sufficient but plug a power strip into it to distribute the power, and watch the load.

 

[grow nerd]

Not much in terms of electrical / wire capacity & temperature limits. It should be plenty safe to run 400w & change on a #14 (15A or 12A @ 80%).

 

[THCV]

The problem with that math is it doesn't take into account inductive reactance/power factor. My 150w HPS uses 3 amps startup current before it settles down to 1-1/2 amps. A 400W HPS/MH lamp on a magnetic ballast could draw as much as 9 or 10 amps startup current for a couple minutes. That said, a 12 AWG cord is probably sufficient but plug a power strip into it to distribute the power, and watch the load.

a couple minutes? more like a few seconds and certainly not long enough to trip the breaker. either way, when i said his total is still under 10A, i still think it's true. I have run 6 1Ks on one 240/30A circuit with 10AWG wire for YEARS without problems. That's up to 30A total if you are conservative (but 15A per wire, totally manageable and up to code) and say 1100W/220V per light. Still, no problems given the 10AWG wire. I wonder what massive multi-minute amperage rush you would imagine with 6 1Ks! LOL

I would and have plugged a 400W into a standard 16AWG extension cord with zero problems. Don't sweat it.

 

[Batboy]

Awesome. Thanks

 

[sparkjumper]

THCV is right.Much too much emphasis is placed on "start up current" I've noticed through the years.I've used clamp on ampmeters to try and get a reading on startup current and its so quick apparently the naked eyes cant see it.At least mine couldnt.Anyway after years of growing and decades of being an electrician,dont put much emphasis on "startup current" when sizing wiresize for different circuits.Its just not much of an issue in reality.I ran two 1K vertizontals and an 800W combo on a 240V 12 wire 20 amp circuit for a couple years with no problem.I decided I wanted 3 1K verts and move my 800 combo for veg and that 200 watts was enough to start tripping my breaker.I had to switch to 10 wire and put it on a 2 pole 25 and no problems since.My point behing this story is the breaker never tripped during startup,it tripped about 15-20 seconds after being energized.Startup current is just nothing to be concerned with in my experience.Two things, voltage drop after 100 ft. you want to upsize one AWG size and the 80% deration rule for continuous loads.These are real concerns as opposed to startup current concerns

 

[grow nerd]

Definitely agree with THCV and sparkjumper on the wire size / "start up current" issue.

 

[Lazyman]

Besides the good advice on wattage and distance above, please be sure to keep your cords off the floor! Stepping on cords breaks them down and wears on the insulation. Over time this can cause a bare spot, then you just add some water from a spill and ZAP you're in trouble. Not safe to have any power touching the ground.