How do I electrically map my
Caution: electricity is dangerous and an
accident could possibly be fatal. Respect electricity.
Be cautious and never rush yourself.
the electrical design of your house will provide you
with necessary info on what lights, switches and outlets
are associated with which circuit breakers (or fuses).
This will also help you in knowing what the electrical
limitations are for each of those circuits.
it will save you money by saving the electrician time
not having to figure this out from scratch on his/her
own... in any project now or future.
2. it will show
you what amperage rating you have for every circuit
3. it will show you how much power you will be able
to use safely in your grow room
4. it will tell you
whether you need to move high draw devices (Such as A/C)
to different circuits.
5. it will tell you how many
circuits are available for your grow room area
Making the Map:
(if you have a
friend this will the following process will go smoother
and take less time)
1. Draw up a map of the
floor plan of your whole house on paper and mark on it
every outlet, switch and light fixture (not plugged into
2. find where your breaker panel/fuse
3. You can use an outlet tester, a volt
meter or even a plug in lamp (or use a radio) if you
don't have an outlet tester or volt meter. Outlet
testers are easier to use, indicate polarity, ground
faults and other electrical problems.
4. note on
your map the outlets that are controlled (on/off) by a
light switch and mark them on your map (some outlets are
split...meaning only one of the two plugs are controlled
by the switch ..the other is constant)
5. go to
a working outlet and test your tester/meter/lamp/radio
6. turn off one breaker (or pull one fuse) ...
not the main for the whole house though
around checking every outlet and light in the house and
mark on your maps which one lost power for that
particular breaker/fuse.... use your tester/meter/lamp
in the outlets.
8. when done checking the
house.. turn on that breaker again.
steps 6, 7 & 8 until you have all the breaker/fuses,
outlets and lights mapped out for your house.
10. Write the general info on your breaker panel
in permanent maker (if not there already)... i.e. BKR1
Kitchen Outlets... (later when you decide what one will
be the Bkr or Bkrs that go to your grow room I would
mark these too, in case of any emergency in the future)
NOW SAVE THIS INFO IN A SAFE PLACE
Now that you have your map:
x volts = watts
amps = watts/volts
you can make sure that what you have plugged in
already on the circuit plus what you intend to plug in
with your grow room... won't overload your circuit ...
I usually recommend, in these types of installs,
a max of 75% of the rating on the breaker or fuse is
ever used for that circuit. Meaning if there is a grow
light, or an air conditioner, or pumps etc...on a
particular circuit, total them all up.
are on a 15amp circuit, for example, I don't like to put
more than 11.25 amps total on that circuit ever... so
you don't have to ever worry about start up currents
being near the level of your breaker tripping.
Most bigger grows need
to be in the basement room where the breaker box is
located. This keeps the ballast cord runs as short as
possible (run cooler, less resistance and line losses).
Smaller grows can be located near 220V plugs
(i.e. clothes drier, or even the oven). If you want more
power, use existing 220v sources (Such as clothes dryer
and oven plugs). Hydroponic stores often sell pre-made
timer boards that plug right into a 220v source, with
appropriate 110v outlets.
Cabinet and veg room
grows can make use of room power outlets - care should
be taken to run off different circuits. You can use a
grounded extension cord to tap into a circuit in a
different room if your main grow room is on one circuit
and you need another 15 amp circuit.
breakers trip thermally when exposed to
higher-than-rated current draws. This means an
overloaded circuit will take a while to trip the breaker
normally this is safe, but older house wiring may not
like extra heat.
When you have made any electrical additions, make
sure everything is kosher by checking the normal
operating temperature of the plugs (with the back of
your hand). If a plug has become unreasonably warm or
even hot, unplug the device (usually a ballast).