So here you can see an example of an off-grid system. And as you can see the system consists of several components and I’m gonna introduce each in this video. Let’s start with batteries. Batteries store the solar energy. Solar batteries work by storing the DC energy being produced by solar panels and giving it back to you when you need it .
There are different types of batteries used in solar systems and you can choose them according to your specific requirements.
Here the batteries are connected in series with each other to increase the voltage of the system. Each battery has a positive and negative terminal, and you can connect them in parallel or series to change of voltage and the capacity of your off-grid system. This is the charge controller. It manages the power going into the battery bank from your solar panels.
It also ensures a healthy charge profile for the batteries, and stops the power running backward to the solar panels overnight. Typically charge controllers come in to two technologies: the maximum power point tracking or MPPT and pulse width modulation or PWM. And this controller is an example of an MPPT charge controller. this is the Inverter. Inverter converts the direct current or DC output of the batteries into the alternating current or AC, which enables you to power your AC equipments with the use of batteries.
this is the monitoring device which will be connected to the charge controller and is responsible to provide you with information about your solar set such as voltage, current, power, temperature and so on.
DC and AC breakers provide methods for us to stop current and voltage being supplied to the equipment, so when we would like to remove or service those items, or in the event of an overcurrent, they come really handy. solar panels and batteries are the DC sources. Therefore DC switches are used for solar panels and batteries. DC switch is connected to the inverters output and protects the inverter and consumers in case of abnormal conditions.
So using the AC switch, we have the control over the AC output. Okay there are lots of connections here. Let’s find out how to wire the off-grid system. Two connections come out of the batteries. One from the positive terminal and the other from the negative terminal.
Battery positive goes to the charges positive battery terminal and bettery negative goes to the charges negative battery terminal. The bus bar makes it possible to split the connections. This means that the positive is connected to two places and the negative is also connected to two places. Then the negative connection once goes to the charger and inverter and the positive goes to the charger and inverter.
This is called the rail or din rail which is a metal strip that is used for securely attaching electrical and industrial control products such as circuit breakers or terminal blocks and here we mounted our switches on it.
Ok I remove the cover here. here I have the PV positive and negative terminals, battery positive and negative terminals, and DC loads positive and negative terminals. Turning this DC switch on will connect the batteries to the charge controller and will turn it on.
As you can see the charge controller is on and it’s displaying some parameters on its LCD. turning the other DC switch on will connect the solar panels positive and negative terminals to the charge controller.
Now I turn the inverter on and turning the AC switch on will bring the power to the plug. So I plug an AC consumer like this drill and it will let me use my AC equipment. in next videos we will talk about each component in more details