Electrical & safety

[lkdj2003]

How do I convert watts to amps and amps to watts?

The formula for converting Watts to Amps is : Watts = Amps * Volts

The formula for converting Amps to Watts is : Amps = Watts / Volts

SAFTEY WARNING : Only use 80% of the circuit breaker capacity!

Common Conversions North American and other 110 volt countries

Lights :
1000W / 110V = 9.1A
600W / 110V = 5.4A
400W / 110V = 3.6A
250W / 110V = 2.3A

Circuits :
10A * 110V = 1100W and 80% safe usage is 880W
15A * 110V = 1650W and 80% safe usage is 1320W
25A * 110V = 2750W and 80% safe usage is 2200W
30A * 110V = 3300W and 80% safe usage is 2640W

Common Conversions British Commonwealth and other 240 volt countries

Lights :
1000W / 240V = 4.1A
600W / 240V = 2.5A
400W / 240V = 1.7A
250W / 240V = 1.1A

Circuits :
10A * 240V = 2400W and 80% safe usage is 1920W
15A * 240V = 3600W and 80% safe usage is 2880W
25A * 240V = 6000W and 80% safe usage is 4800W
30A * 240V = 7200W and 80% safe usage is 5760W

Remember that a circuit services more than one power outlet.
A two outlet wall plug will use only one circuit.
There will be more outlets on 240V systems per circuit than there will be in 110V systems.

[lkdj2003]

Don't use one of those adapters that converts a 3 prong to a 2 prong unless you know for certain that the socket has been properly grounded.

You can install a new breaker in the service panel and run 3 wire Romax to your grow. Then you can install a 3 prong outlet (preferably a GFCI). Buy a basic wiring book and follow the instructions exactly. Electricians don't charge much compared to morticians, so don't be afraid to hire a pro.


Add a 20 amp, not a 15 amp. The cost is the same and the 20 amp is no more hassle than the 15 amp. While you're at it, consider installing 2 runs of wire so if your grow ever needs another breaker, the wire will already be in place.



Additional note: Adapter tab must be screwed to the outlet center screw.

Bad solution all around, as most residential outlets without ground are fed with circuits lacking ground. False sense of security can kill you.

RE: Additional circuit run. That second circuit, when run correctly, should be what is called a 3 wire circuit (Line 1, Line 2, Neutral, Ground), Can provide 240V as well as 120V, and when properly ballanced, halves the voltage drop in the wires.

Difficulty: One extra conductor.

[lkdj2003]

Normal household timers are not designed or rated to deal with the inductive power load used by horticultural lighting. Go to your local Hydro shop and buy a contactor relay like this one. A contact relay switch is required so that the timer turns on the contactor which then turns the light on.

Almost all new growers will experience this failure. The reason for this is the contacts in these timers are not sufficient for the job. Household timers are rated for a RESISTIVE load, ballasts present an INDUCTIVE load, (a very large surge at switch on) this fuses the timer contacts together = Timer failure.

What is a relay switch?

An electro mechanically operated switch.

Contact relay:

[lkdj2003]

Many people have used these lights in their homes with no problems what so ever for thousands of hours. Good safety measures and common sense are to have smoke alarms inside and just outside of your grow area. Especially if your grow area is in your basement have a smoke alarm positioned so you will be able to hear it from the upstairs bedroom.

Not without risk. Proper garden design from the start will minimize these risks.

No1 Rule: Safety!

[evo]

While normal household timers are not designed for such a high charge, you can find some that are.
Argos sell a pair of digital timers that can take up to 3120W from an inductive charge.

What this means is if you have a digital ballast, say, from Lumatek, you can safely use this without a contact relay, as long as your timer can sake at least 3x the charge you are using (for safety).

This is down to the soft start in digital ballasts, unlike the "hard starts" of there magnetic cousins, meaning the charge running through the timer never gets high enough to melt the fuses.

So, good digital timer + good digital ballast = perfectly safe to use without a contact relay.

[Packer27]

Was thinking off starting a little side line in "indoor garden" electrics, as a spark it would be no problem only thing is in getting people to trust in discertion shown, any sugestions dudes and dudets ?

(.)(.)

...FTW...

[matbigpen]

If i was to use a self ballast 125/200w ctf light could i use houshold timers then? or would it still be quite dangerous?

[Monobrow]

ctf light?

[matbigpen]

sorry cfl

[cornz]

No, as CFL are self ballasting, they will work fine on the standard timers..