I’ve been thinking about grow safety lately so the following is some of the things that came up when I was looking at my own grow. There is tons more to add and I would love to see this thread grow so please feel free to add any information or links that you think would be relevant or helpful when it comes to grow safety.
Small disclaimer – The following electrical information is only to be used as a rough guide and is not meant to be specific to a single situation. Each country, state/province or area is going to have their own laws regarding electrical installations as well as their own power distribution methods (50hz vs 60hz) so please make sure to consult a local professional with questions or to carry out work on your home.
Grow Safety Basics
Electrical
-
Circuit loading basics
-
Your power requirements for each device (lights, fans, etc etc) in your grow will be measured in Watts (volts x amps). The watts will be listed on the device or in the manual. Add all watts together to get a total power usage for your equipment on each circuit.
- E.G - Lights 600W + fan 100W + heater 250W + exhaust fan 300W = 1250W
-
Each circuit within your house will be able to run a safe amount of watts, depending on the wire and breaker size. The two most common circuits within residential properties are 15A and 20A circuits. Check the circuit size by looking at the amperage amount listed on the breaker.
- 15A circuit breaker (#14 American wire gage) = 120V x 15A x 0.8 (in Canada, for continuous loads, you must derate circuit to 80% capacity for safe operation as per CEC) = 1440W
- 20A Circuit breaker (12# AWG) = 120V x 20A x 0.8 (continuous Load) = 1920W
- These are the amount you can safely load a 15A or 20A circuit (within Canada, In other areas but please check your local electrical codes and consult local professionals)
- Make sure you know exactly what electrical fixtures (plugs and often lights) are tied into each circuit so that you know exactly what is drawing power from that circuit – Turn off the breaker and test each receptacle and light in your house to determine what each breaker/circuit is powering.
- Side note – Fans and other motorized equipment will have an “in-rush” current when starting. These can cause very brief spikes in power demands on a circuit. Try not to have all your motorized equipment come on at exactly the same time to avoid nuisance tripping with the start up in rush current. (these motors are very small so unlikely to be an issue but worth mentioning)
-
Extension Cords/power boards – A chain is only as strong as its weakest link, the same is also true for electrical circuits. When loading a circuit, you must consider all connection points including your extension cords and power boards.
- Problems with power boards can arise from:
- Overloading the power board
- Dust built up in unused ports.
- Power leads becoming dislodged over time causing arcing.
- Poor placement of power cables and extension cords leading to the power board.
- Inadequate ventilation of the power board preventing “normal” dissipation of heat generation.
- Limited understanding of the amount of power being drawn by different appliances. Just because a power board has 20 receptacles does not mean you can plug in 20 devices. Make sure you treat the power board like any other connection points and only connect a safe number of devices, based on their loads demands and power board safety ratings.
- Extension cords will come in many different wire sizes, insulation ratings, location ratings and power rating. Make sure you have the right cord for the job
- Make sure you factor the extension cords wire gage into the equation when calculating power demands on your circuit
- 14AWG = 15A / 12AWG = 20A (these are rough guides and there will be exceptions, read the labels/instructions and be sure to understand what is considered safe usage for your cord)
- Voltage Drop – over long distances, voltage will drop in electrical circuits meaning the circuits have to produce more amps to provide the loads required power. Additional amps may compromise the wires insulation or overload your breaker and more amps = more heat. Try not to use long extension cords (or really any extension cord) if you don’t have to. If you are curious about voltage drop distances, there is table D3 in the Canadian Electrical Code that has a formula for working out voltage drop based on wire size and distance.
- Problems with power boards can arise from:
-
-
Fire Safety Devices
-
Smoke Detectors
- Generally, there are two types of home smoke alarms: photoelectric and ionization.
- Try to ensure you interlock your smoke detectors to ensure you are alerted in all areas of your home
-
Fire Extinguishers
- I highly recommend having a fire extinguisher in the house at all times
- Types:
-
* Make sure your fire extinguisher can be used on electrical fires (Class ABC)
- Automatic Fire Extinguisher Ball – These are a means of passive fire protection. Different models can function in slightly different ways, but the basic idea is the same. An activation or trigger strip is embedded into the ball’s outer casing, which holds the dry fire extinguishing powder inside. When the trigger is exposed to flames for more than a few seconds, the casing will burst open and disperse a cloud of chemical powder in the immediate vicinity. A fire extinguishing ball can usually put out the flames in an area with a radius ranging between 4 and 5 meters. An audible warning such as a bang or other loud noise is set inside to alert those nearby.
- The devices work as passive protection (without human intervention) in 3 different ways:
- Flame detection – activation occurs when heat or flames are sensed by the trigger
- Alarm – a loud noise alerts those nearby that there is a fire
- Fire extinguisher – the dry chemical agent reacts quickly and effectively to suppress the flames in the immediate area
- The devices work as passive protection (without human intervention) in 3 different ways:
- Dust and water
- Dust and water/moisture are very bad for motorized devices and electrical connections. Dust and corrision will gradually ruin electrical connections causing arcing and other issues. Water can cause short circuits that can also lead to fires.
- Power boards should be kept off the tent floor and be secured in place to ensure the cords do not become lose and start arcing.
- They should be kept away from possible wet locations (tent floor)
- Dust and water/moisture are very bad for motorized devices and electrical connections. Dust and corrision will gradually ruin electrical connections causing arcing and other issues. Water can cause short circuits that can also lead to fires.
The only thing I might add is checking the temperature of your higher current plugs once a month.
