In our last video we showed you our new outdoor rated mounting box. Check out here: https://youtu.be/mMLPZ7OC2f4 .
Also in an earlier video we explained how these boxes are built and what each element do. Check out here: https://youtu.be/NjEKdbfhI84
But still we got many questions related the components. So let’s go through them one-by-one, if you haven’t seen the second video I definitely recommend to check before you go forward.
You can image this as a backbone for a person. Although this is an optional item if the unit is not box mounted, we strongly suggest using this feature anyways to have a more convenient way to integrate the subunits and the external components. If you don’t use a box you can also mount your complete setup to the wall by the DIN rail.
The rail is a standard Top-hat or Type O DIN-rail with 35mm height. In the US mainly referred as TS35. We normally recommend the 7,5mm (normal) depth version.
If you want to add any extension to your AquaShield system you can also buy “Rail mont” components so you can easily add or remove these components from your setup. All the below listed items are available in Din rail mount style.
The unit works with 12V DC (direct) voltage. In your home electrical system the sockets have 110V AC or 230V AC (alternating voltage). If you connect directly AquaShield to your electrical socket it would be destroyed immediately and it is also dangerous. So we need to convert this high AC voltage to 12V DC.
Our recommendation is to use MeanWell MDR-60-12, that you can also buy from us as part of your package. This works with 110 and 230V AC systems as well, so can be used basically all over the world.
The circuit breakers are protection against the short circuits and the too high power consumption in the system. So this is for protecting the device and the cables from overheating and potential fire in case of too high power consumption or an internal short circuit.
Make sure that the components (pumps, lamps, fans, heaters etc) sum power consumption (operating current) is lower than the design of the protective device.
Example: If your circuit breaker is rated for 10A and you live in the US where the single phase voltage is 110V, then you can use approx. 1100W power (sum for all your equipment). Please note that this power value changes by the voltage of your electrical system, hence your location. (ex.: US – 110V, EU – 230V), AU – 230V etc)
GFCI – Ground Fault Circuit Interrupter
Or sometimes referred as Residual Current Device (RCD). This is directly protecting the human life against electrical shock. The purpose of the earlier device was protecting the equipment and indirectly human life by preventing overheat, this device is protect human life by breaking the electrical circuit if potentially deadly current (larger than 30mA) is going any other than the normal path. (the normal path is the live and the neutral cable, the dangerous is through your body to the ground). Please note that this item has also a max operating current rating and it has to be at least equal or larger than the circuit breaker. And we recommend to have the trigger current max 30mA.
Since the unit is used for aquaponics or hydroponics and both are water related operations, we strongly recommend to always use GFCI in your system. If the socket or electrical feed (in your distribution panel) has GFCI integrated this item is not mandatory, but makes no harm to have double protection.
The relay is nothing more than an automated switch, or you can image as a strong buddy who helps you lift the heavy bags if you ask him nicely. 🙂 At home when you wanted to turn on a pump or a fan you either flip a switch on the wall or plug your equipment – and by that you close an electric contact – and the electricity starts to flow. By your very small effort a huge machine can start. The relay is the same just the flipping (or plugging) – aka making the electrical contact – is by an automated command with a small power.
Aquashiel Control Module has only a limited power so it can’t switch big fans or pumps directly. Its strong buddy is the relay. And we can choose the best fit option for all the different purposes. So if you want you could start even an industrial size pump as well. The relay also helps to protect your Aquashield from electrical shocks that could came from your equipment and the cables, especially if it is mounted outdoor. (ex.: short current, lightning strike etc)
The relay we use should have 12V DC coil voltage and it is very important to choose the rated switching current of your relay based on your need (the size of your equipment). If your equipment or your need changes no worries. Your AquaShield is still perfect you need to change only the relay to a different one with higher current (power) rating. Your relay’s current rating has to match also with the circuit breaker’s current rating. The relay’s current rating has to be equal or larger, than the nominal current of the circuit breaker.
Example: If you have a 500W grow light that you want to switch and you live in Australia where the electric supply is 220V. It will require 2,28A current. If you choose an 8A relay probably you are good to go. But in each case you need to double check, because it is also important to take into the consideration that the relay rated current is for “Ohmic load”. For motors, fluorescent grow light and for many components you need to de-rate this nominal value. If you use a 2-3 safety multiplier you are good to go in the most of the cases.
How you can connect your equipment to the relay
If you using an indoor application and the humidity is not too high at the place of install of your AquaShield Controller, you can connect your pump, fans, light via normal sockets. These are also available also DIN Rail mounted form. In this case you need just plug your equipment as you would do to a wall plug, but you don’t need to disconnect because and the relay will turn on and off the power to the socket for you.
If you install outdoor or into a high humidity ( >80%) and all the places where water splash or condensation is expected, then we recommend to use a fully enclosed IP55 / NEMA 4 or stronger box. In this case all the cables are entering the box via cable glands. In this case the electric plug normally not feasible (can’t be push through the cable gland). So you connect the wires of your cable to the relay socket.
Most of your equipment requires grounding (or earthing), typically the ones with metal casing. It is important because if the equipment has an internal short and the live (or neutral) cable touches the casing while you holding the equipment, the high voltage electricity will goes back to the ground through this cable and not through your body. With this said your power supply to your Aquashield – box mounted or not – needs to be grounded and the socket where you plug as well.
If you use DIN rail mounted socket to connect your equipment to your Aquashield system (as shown above) it should be a grounded version and your main power supply ground should be connected to here as well. As an example for the ground wiring please see the Control box building video https://youtu.be/NjEKdbfhI84?t=291. The ground cable color should be green or green with yellow stripes. (can varies by local rules please check).
If you have a box with cable glands and your equipment is directly connecting to the relays (you have no plug at the end of your equipment cable), your box should have a ground bar. This is just a piece of metal bar with screws where you can connect multiple wires. This can by rail mounted or otherwise fixed somewhere in your box. The ground wire from your main supply and all the other ground wires should be connected to this bar. If it is more convenient you can use a ground bar in case of DIN rail mounted sockets as well.
Wires are also an essential part of your control box. It is important to select the type and the size of the wires based on the circuit breaker rating, and not on your actual load. Depend on the cross section and material the wires are rated for a nominal current Always check its rated current before use a wire. The wires also color coded based on their use (live/hot, neutral and ground/earth/PG) follow the local regulations especially for the “high voltage” AC cables.
The wires can be solid, also called solid-core or single-strand or stranded (a lot of smaller wire stranded or wrapped together to form a larger conductor). The stranded wires is more flexible and if your motor or fan vibrating this is much more preferred, but you have to always use a ferrule to connect it to the relay socket or to the ground bar. The ferrule is a metal casing that needs to be crimped to the stripped wire to hold them together when used in a screw terminal.
IMPORTANT: If you want to build your own control box or add electrical components to your existing setup, please consulate with a certified electrician about the selection of the items, the local rules and regulations. Only use labeled and certified components.