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andycapp
22nd September 2007, 05:46 PM
My wife and I have recently become interested in indoor hydroponics and grow orchids and assorted vegetables in a spare room of our rental house,
We are moving house to another rental property and we want to increase the quantity of lights we use. We currently use around 1000W of equipment but are planning on using 8000W in the new house.
I have been told that this could trip the 'breaker' and we should run a specially made timer box.
Is this true? Does anyone have suggestions as to what we could do?
As it is a rental we can't modify any house wiring or the fuse box - we can only use the available circuits.
We don't really understand how electricity works either...

Hope to get some response,

andycapp :)

K_S
22nd September 2007, 08:10 PM
When your "somewhere out there" you could enquire of the local council if your allowed to have a temporary power pole installed (like a builders pole) to bring more power for your hydroponics.

Just a thought - good luck

Tools
22nd September 2007, 08:54 PM
:smokeing:

aussieorchid
22nd September 2007, 08:56 PM
What equipment are you using that is drawing so much power if it is lights you will need to have a way to cool teh room with that much lighting will come a lot of heat.

Master Splinter
22nd September 2007, 09:03 PM
You'd better really love orchids.....

Go and check your meter box and start playing around with circuit breakers to find the circuit that you will be running the lights from.

I'm assuming that you are running the lights from a power point - just plug something in, like a radio or light and turn it on, then go to the meter box and flick the circuit breakers labelled "Power" (you may have one, two or three of these, typically) one by one till the light/radio goes off - and that'll be the circuit that you want to look at.

Check to see what else is on that circuit (see what else doesn't work while its off), and work out the demand on that circuit. (if its a high draw circuit - it has the kitchen kettle, toaster and washing machine on it, you may want to see about using a different circuit for the lights)

Circuit breakers are rated in amps - the normal household power circuit is something like 16 amps, I think. (not a sparky so don't quote me on that!)

The magic formula is Watts = Amps x Volts
2,400 watts = 10 amps x 240 volts.

So 8,000 watts of lights (33 amps) will need to be spread over at least three 16 amp circuits to avoid tripping the breakers; and good luck if you want to put the kettle on!

It'll also be costing you about $1.20 per hour to run, or about $200 a week if you have them on 24/7.

Also figure out what 8,000 watts worth of heat is going to do to the room! (hint - that's more than enough to turn a room into a sauna three times over!)

And if you are drawing that much extra power continually, don't be surprised if you get a visit from the drug squad early one morning; really high residential power consumption is one of the tell-tale pointers that there's hydroponics activity for a certain crop going on there. (why they set up in residential areas is beyond me - hire a shed in an industrial area, you get better privacy and the power consumption won't be out of place!)

Tas_Dean
22nd September 2007, 10:18 PM
^^^^

What Splinter Said. If you start dragging out 8KW, without the local power authority receiving a notice of installation for a large load (heater/multiple heaters, etc), you would almost definitely cop a visit from their inspectors after your first power bill, with police/drug squad present as backup. Aurora Energy (Tasmania's electricity supply company) have several employees whose main job is checking out usage changes on properties.

8KW is the size of heater I would spec to heat a room 6 Metres by 10 metres in Tasmania, and that's thermostatically controlled, to heat a room to about 21 degrees it would probably only run for 15-20 minutes per hour in the middle of winter, and that's less than 8 degrees outside. Your looking at serious heat generation, and serious power bills.

Splinter, your maths and knowledge there is pretty spot on!

elkangorito
22nd September 2007, 11:51 PM
My wife and I have recently become interested in indoor hydroponics and grow orchids and assorted vegetables in a spare room of our rental house,
We are moving house to another rental property and we want to increase the quantity of lights we use. We currently use around 1000W of equipment but are planning on using 8000W in the new house.
I have been told that this could trip the 'breaker' and we should run a specially made timer box.
Is this true? Does anyone have suggestions as to what we could do?
As it is a rental we can't modify any house wiring or the fuse box - we can only use the available circuits.
We don't really understand how electricity works either...

Hope to get some response,

andycapp :)


There is only one way to achieve what you want & that is to install a dedicated 40 Amp circuit with an outlet, the outlet being placed at the desired location OR three extra 16 Amp power circuits. Obviously, you will need permission from the landlord to carry out this work & you will have to pay for it.

The next problem you will have will be with your maximum demand. It is quite possible that the addition of an extra 33 Amps of load, may very well trip the main circuit breaker or blow the 'service fuse' (if you don't have a main circuit breaker). If the maximum demand calculation indicates that you have exceeded the capacity of the consumer mains, the mains & the Main Distribution Board will need to be upgraded (at a further cost).

You will not safely & effectively achieve what you want to do by mucking around with 16 Amp circuit breakers.

BTW, I am an electrician.

andycapp
23rd September 2007, 05:42 PM
Thanks very much for the info everyone! :D

Yeah I'm sure that the cops will probably visit after what you have said but that's ok - there's no illegal activity going on.

Sounds like it will have to be downgraded as I can't ask for mods to be done on the house.

So you are saying that the maximum draw from a power outlet I can run is 2400W?
That is only 2 lights - just one more than I currently am. Darn.:~

What is they are flip-flopped so I can run 2 1000W lights for 12hrs then the other two in a separate room for 12 hrs? That would work huh?

*When you are flowering vegetables they need at least 12hrs of dark to flower properly for any one who doesn't know.

Yeah the electricity is a lot but we don't have any other hobbies.

andycapp :cool:

Pulse
23rd September 2007, 05:56 PM
I'm sure any landlord would be happy for you to install an extra power circuit or two, just pay for a safety switch RCD or offer to get all the old fuses swithced over to miniature circuit breakers MCBs. You could add two 20A power circuits but as discussed you are exceeding the normal calculated maximum demand for a house and may well blow the service fuse...

Cheers
Pulse

elkangorito
23rd September 2007, 09:17 PM
My comments are in red.


Thanks very much for the info everyone! :D

Yeah I'm sure that the cops will probably visit after what you have said but that's ok - there's no illegal activity going on.

Sounds like it will have to be downgraded as I can't ask for mods to be done on the house.

So you are saying that the maximum draw from a power outlet I can run is 2400W?
That is only 2 lights - just one more than I currently am. Darn.:~
Yes. Even though the cable of a power circuit is rated at 20 Amps, the power point is only rated at 10 Amps. Installing power points that can handle higher current ratings is a possible solution but by doing so, other problems will be introduced. Not a good idea.


What is they are flip-flopped so I can run 2 1000W lights for 12hrs then the other two in a separate room for 12 hrs? That would work huh?
Yes.


*When you are flowering vegetables they need at least 12hrs of dark to flower properly for any one who doesn't know.

Yeah the electricity is a lot but we don't have any other hobbies.

andycapp :cool:

DavidG
23rd September 2007, 09:29 PM
Why not use UV fluorescent lighting?

elkangorito
23rd September 2007, 10:13 PM
Why not use UV fluorescent lighting?

I don't know what kind of lighting is being used by andy but for this kind of arrangement, mercury vapour lamps are normally used because of the amount of UV they radiate. Fluorescent tubes without the white phosphor coating produce UV & are used in the growing of plants but the UV levels produced by a fluoro tube are low compared to a merc vapour.

andycapp
24th September 2007, 03:08 AM
Fluros are useless except for starting seeds or clones that are freshly cut.

HID's (high intensity discharge) lights come in both Metal Halide or High Pressure Sodium.

MH's throw a spectrum of light that contains more blue making them better for vegetative growth.
While the best for flower time is the HPS. It throws a red/orange light that is high in the red spectrum and encourages flowering.

You can get 130W Enviro-lights or CFL Spectrum bulbs that are available in different intensities such as 5400K and 14000K but again they are only really strong enough to keep a plant in suspended animation such as a mother plant that will not be flowered and used as a donor of cuttings for future crops.

Thanks again for the advice! :U

andycapp

Amb
2nd October 2007, 11:56 PM
Excuse me, and correct me if I'm wrong, but I thought the 8000 W is the light output, it's not how much current the lamps will draw. You have to check the plate to find the input current of each light fitting, then work it out. Yeh I know the threads a bit old, but couldn't resist.
Chalk up one for the non-lectricians. :p

Master Splinter
3rd October 2007, 02:02 AM
Well, if we want to work it out for 8,000 watts of light output, we need to allow for the efficiency of the type of lighting, (http://en.wikipedia.org/wiki/Luminous_efficacy) and factor this in to get an idea of how much current will be drawn by a particular lighting type to get to our desired light level.

At the worst end of the spectrum, a standard incandescent bulb is basically a heater with a tiny bit of light output - they offer about 5% efficiency at best.

That means you will need to pour in 20 times as much power to get your 5% worth of light (8,000 watts), so you are looking at 160 kilowatts (20 x 8,000). There are furnaces for smelting aluminium with less of a current draw than that!

My really kludgy maths-in-the-head works that out as being able to heat a standard bedroom to over 2,000 degrees (assuming it takes 2,000 watts to warm a room by 25 degrees).

HID lights are (roughly) about 5 times as efficient; that gets our room heating effect down to a 'mere' 32 kilowatts or a toe warming 400 degrees.

elkangorito
3rd October 2007, 04:14 AM
Excuse me, and correct me if I'm wrong, but I thought the 8000 W is the light output, it's not how much current the lamps will draw. You have to check the plate to find the input current of each light fitting, then work it out. Yeh I know the threads a bit old, but couldn't resist.
Chalk up one for the non-lectricians. :p

A Watt relates to electrical energy with regard to this subject - the OP is talking about electrical Watts.

What you're talking about is the luminous efficacy (not "efficiency"), which is the ratio of the total luminous flux produced (in lumens) to the total electrical input power (in Watts).

NCArcher
3rd October 2007, 10:11 AM
Excuse me, and correct me if I'm wrong, but I thought the 8000 W is the light output, it's not how much current the lamps will draw. You have to check the plate to find the input current of each light fitting, then work it out. Yeh I know the threads a bit old, but couldn't resist.
Chalk up one for the non-lectricians. :p

You really should do your research before you start 'chalking one up'.