Sir, what about a breaker in between the charge controller and the battery? The direction of current flow is from the charge controller to the battery. There is the myth that the battery has the higher potential and for this reason , the DC breaker ++ should be directly connected to battery +. But I still do not agree . I hope they are not mistaking the charge controller with the inverter . Sir, throw more light .
@@soloado5084 great question, for this exact misunderstanding of polarity DC Breakers, we have to move on towards Non-Polarity DC Breakers that are designed specifically for DC Current. But the basis are still the flow of the current, the source would be the PV Modules to the batteries. Think of the batteries as a dam of water and the solar panels is the rain flowing down the river into the dam. Although the dam has much more cubic meter of water, the flow would only be out once the dam is full to overflow or pumped out. I won't declare this as excacly but in principle the it is the same.
@@lowtech_1 it certainly is, therefore just stay away completely from polarity breakers and get to Non-Polarity breakers. Source is the power towards the Load. Source would mostly be PV Panels, load would be MPPT towards battery or inverter convert DC to AC(load). Another reason why DC Breakers aren't commonly uses from battery to the inverter and that Fuses is still in use. Because the batteries would be the source towards the inverter(load). Non Polarity breakers are used by battery manufacturers, as it certainly has benifits compared to fuses. Thermal protection, overload protection and short circuit protection.
great video, i saw lots of videos on this topic on youtube but many of them were non technical persons and could not satisfy me, your video gave me 100% understanding, if possible please mention how to identify polarized and non polarized dc breaker physically
@@Iqbal_khan-9 it would be best be shown on the diagram. Flow in one direction are Polarised breakers, also has magnet in, use small washer to feel if there is a magnet pulls or push. Normally Non-Polarity breakers will mention it clearly on it and show + / - on each pole
So I have seven panels just like in your diagram. If I am left with 250 volts and 10 amps presumably that is DC output. Is there an inverter and battery that can take this? I have looked into putting three panels in series and then putting a string of three others in parallel but this would leave the seventh panel not used. Thanks in advance for any advice
@@ltvtech hi I’m in uk actually, yours was the only video I found with seven panels. I bought seven as it is the perfect length for my carport. Thank you for your reply
@@timdougall5415 in the UK, Grid-tied inverters are very popular. If you go Grid-tied SolarEdge and SMA are popular. If you going Hybrid, Sunsynk witch are UK based is also good. I personally like Transformer based (Low Frequency) inverters like Victron from Netherlands. Hope it helps.
Great video.i have connected two strings in parallel each string has 5 panels and each panel has aroung 575 watt,48vdc and 14.8 amps.the panels i am using are bifacial.each string gives out around 14 amps and if i connect these in parallel it will give out around 28 amps.what rated mcb should i use to connect all these 4 wires i for parallel connection?plz help.thx
It is a common practice to include a safety margin of 25% to ensure the MCB can handle slight overcurrent conditions without tripping unnecessarily. This margin accounts for variations in sunlight intensity and temperature, which can affect the current produced by the panels. Safety Margin CURRENT = Total CURRENT × 1.25 28 AMPS × 1.25 = 35 amps Select the Circuit Breaker Rating: The MCB should be rated slightly above the calculated safety margin current. Standard DC MCB ratings are usually available in steps such as 32A, 40A, 50A, etc. Since 35 amps is not a standard MCB rating, you should select the next highest rating. In this case, a 40A MCB would be appropriate. Remember the fuses as well for protection of reverse current on each string 4 fuses and would be 20A Select it wisely, search Depending how you will parallel it, you would either get 2P 40A DC MCB Non Polarity.
No DC Volts and AC Volts and equipment are totally different. Your DC will also change alot depending on the sun. You might look at Micro inverter if you want to work from the panels
They are cheaper, if used correctly they do the job, but it is very confusing for lots of people, installers etc. The problem will be human error, lots of it in South Africa,
It is very difficult to say on most brands, but use a washer, if it has magnet inside it is polarity breaker. Search and seek manufacturers specs. I want to say if they don't have + and - marking on the terminal screws it mostly would be Non-Polarity MCB
The biggest weakness in any system is the path between the panels and the storage ..controller..the shorter the runs the better it is..power should be immediately to inverter..after its ac then length of wire is negligible.
That is true, we see problems with small scale solar plants with 50 kW-150 kWHigh voltage systems, cables run very far underground in conduit into 1 PV Combiner box in the control room. Technology moves so fast and everyone push to get UN targets for 2030. SAFETY....
@@ltvtech the sadness is. The world nolonger seeks advancement in any tech field.. we are controlled by investors strapped by their over promissed portfolio. WE ARENT MOVING FORWARD. ok getting on the soapbox as you see doesnt work..become scientists again..actually do testing..whats being taught is wrong..in the past we always smiled and went to the lab and tested . Now everyone believes whats on the web..
I saw videos in USA, regulations differ worldwide. But see currently there according to UL they say within 1 meter / feet from the array. SMA on Grid inverters like this. Solar Edge also still inside and lots of arguments... This happen worldwide, technology far ahead of regulations and that also create problems
When it says + or - then that indicates the supply side not the load side. Thats why it's switched from top to bottom as you can feed the supply down the top or up the bottom as long as the supply side polarity matches the diagram shown. Safer solution is to get a 4 chamber/module 2 pole dc isolater (often called a 4 pole isolator) that way you can have the supply side on top or bottom as each pole loops through the breaker twice for fault isolation in either direction. If the fault is on supply side then one of the chambers will extinguish the ark, if the fault is on the load side then the other chamber will extinguish the ark. And the circuit will be broken on both positive and negative.
Thank you Logan, glad it was helpful. South Africa is advancing quickly in renewable energy with our national grid failures. Chinese companies have so many specialists in DC Products, we used to get products from European countries, but they themselves manufacture there and just OEM their brands. Its my passion to dig deep into solar energy and share my experience and quality products. If you have TikTok follow me there on @johanmoesh I dont put all videos on RU-vid. Will in the future create more on RU-vid
