Circuit Protection & General Electrical Safety

In Australia, all electrical works must be undertaken by a licensed electrician. Although this post is not meant to encourage people to start performing their own electrical works, I do recognise that there are a lot of people out there who do perform their own work, and includes information regarding the electrical systems used in residences within Australia. If you are running a large operation, which uses greater than 240V at 20Amps, then the information in this post may not be relevant to you.

This post includes links and legislation that is relevant in Queensland, although all parts of Australia work from the same set of standards, and the legislation around electrical installations is fairly similar.

This post is the first in what I hope to be a number on various topics dealing with electrical issues. If you would like me to add some material regarding a particular topic, please PM me.

Although I have included a number of links off to various sites as reference information, I don't work for any of these organisations so please don't assume that I am trying to spam OS by including information about specific products or suppliers.

Circuit Breakers/Fuses

Circuit breakers or fuses are your first form of electrical protection.

Circuit breakers look like an 'On/Off' switch, and ensure that a circuit only uses a safe amount of power. Breakers are 'tripped' when a short-circuit occurs, or when the circuit is using an excessive amount of power. Breakers are matched to the size of the electrical cable, and should NEVER be upgraded in an attempt to draw more power from a circuit.

In some cases (generally older houses), fuses are used. Fuses provide the same protection as a circuit breaker, although they use a wire link (this is a special type of wire) rather than a switch. Fuses are 'blown' when a short-circuit occurs, or when the circuit is using an excessive amount of power. Fuse links (the size of the wire used) are matched to the size of the electrical cable, and should NEVER be upgraded in an attempt to draw more power from a circuit. NEVER put a larger wire into a fuse than the circuit was designed to handle.

Remember that although there is some safety margins built into the standards used in Australia, these have been put in place to minimise the risk of fire and/or electrocution. A couple of points to note:

• Modifying (particularly upgrading) circuits is a dangerous activity that could result in your death.
• Your home & contents policy probably doesn't cover fire resulting from unlicensed electrical works in a room used to grow pot.
• The fines for unlicensed electrical works (at least in Queensland) are higher than the fines for growing.
• Nothing will bring the emergency services to you house (and your grow-room) like a fire. It doesn't matter how stealthy your grow is, if it catches on fire, you're busted.

Safety Switches/Residual Current Devices

Safety switches help to protect against the most common cause of electrocution (where electricity passes through the body to earth).

Safety switches are very effective at protecting against faulty electrical equipment (eg. light ballast that has a loose wire inside).

Some electricians install devices that are a combined Safety Switch/Circuit Breaker. In these cases, the device performs both functions.

Remember that safety switches make an installation safer, but DO NOT prevent electrocution.

Safety switches should be regularly tested, by pressing the 'test' button. If you test a safety switch, and it does not activate (by cutting the power to the circuit), the device should be replaced as soon as possible.

If you don't have a safety switch available, you should have one installed as a top priority. A few ways to do this for your grow area are:

• If this is your house, have an electrician install a safety switch in the meter box/fuse box.
• If this is a rental, get onto the landlord and ask for one to be installed. In some states, safety switches must be installed into rental properties (this comes into effect in Queensland on 1 March 2006)
• If that isn't possible, or is too expensive, Clipsal make replacement power point (2025RC) that replaces the first power point in a circuit. All other power points on the same circuit are protected by the safety switch (which is installed in the replacement power point).
• Purchase a power board with a built-in safety switch. There are a stack of brands on the market. Some images and details of the ones that I have used before are available here.

General Safety Tips

Indoor grow rooms, in particular those with hydroponic systems, have a lot of water and other fluid in and around the room. We need to make every effort to keep the electricity away from the water. Often this is a balance between space available, equipment available, cost of the setup, and stealth.

A water leak will always drain down, so placing pumps, switchboards, and electrical equioment on the floor should be avoided.

In the interested of safety, some ideas that may be worth considering for your grow rooms

• Try and keep all electrical equipment and cabling towards to the top of the space, and all plumbing and 'wet' equipment down low.
• To allow us to work safety in the event of a water leak, have a remote power 'isolation' switch if possible. This will allow the power to be turned off without the need to enter the room.
  • In the case of a grow cupboard, this just means being able to turn everything off without opening the door.
  • If we are dealing with a room, perhaps a remote switch (in a stealthy location of course) or a dedicated circuit that can be disabled from the meter box.
• Always use equipment that is in good working order - if you are going to run a $20 air pump 24x7 don't expect it to run for 10 years.
• Set yourself a 'maintenance plan' for your equipment. To minimse the change of equipment (and potentially crop) failure, the equipment in your grow room should be maintained and serviced before problems arise. As a example:
  • Water Pumps - Replace impeller every 6 months / Replace pump after 12 months.
  • Air Pumps - Replace pump after 12 months.
  • Seals & Plumbing - Continual checks, repair as necessary.
  • Bulbs - Replace a 50% of the manufacturer's 'maximum life'.
  • Ballasts - Remove all and inspect for damage every 6 months / Replace as needed (depending on manufacturer recommendation).
• Always use equipment that is intended for the environment that you are placing it in, for example:
  • Although fish tank air pumps are not waterproof, most are designed to be somewhat 'water resistant', which minimises the risk of damage from accidental splashing. The use of an air pump designed for something else may not allow for a little splashing.
  • Don't place a water heater designed for a 500L tank into a 100L tank. This will cause the thermostat to be fluctuating all the time, which may lead to failure.

Some of the comments above regarding maintenance and replacement of equipment will not suit every environment. eg. If you are running a HPS light on 12/12 for only 3 months every year, then you would expect to get a lot longer your Ballast, than from one used on an 18/6 cycle that never has a day off.

Tutorial written by Takeshi for cannanation.com/ozstoners.com