In the past,we discussed about the solar cells,Eva,Back sheet of the solar panel.Today we will discuss the junction box and frame as the final part for the ending of this topic.
Frame:
Most customers do not check the frame when they get the solar panels,they thought all frames are the same with aluminium material,so it is no need to check it. But if the frame is too weak,how does the solar panel can be fine for the 25 years or more?
From the above photo you can see the main part of the frame,but how to check the quality when you get the solar panels?
In the market,there are difference thickness for the frames.The standard is 1.3mm thickness frame for 35mm-40mm panel(1640*992*35mm or 1956*992*40mm) and if the supplier plan to make 1640*992*30mm(it is 30mm thickness for solar panel),it is better to use the 1.5mm thickness frame. So when you get the solar panel,you can check the thickness of the frame or feeling by your hand to see whether this frame is strong enough.
Some customers checked the weight of the solar panel to verify the frame is strong or not,it is totally wrong. I saw some supplier to fill the concrete into the frame to make it seems heavy panels,but thickness of the frame is only 1mm.
Junction box:
Junction box is another key part of the solar panel, we all know that there are the diodes inside and it can protect the solar panels when there is the shade on the panel and it is the output device of the solar panel.So it is very important.
Most of the junction boxes are filled with silica gel inside,so it is difficult for you to check whether there are diodes inside or not,so it is better to check with the supplier before you make this order.Some small power solar panels are without diodes inside if you do not check it with the supplier,then it will be problem in the future for the panels.
Some customers thought more diodes in the junction box is better,see the following photo:
Actually it is wrong and the supplier also know that most of the diodes are no any useful,so they will install the low quality diodes inside and there is risk for this kind of junction box.
We also mentioned in part 2 about how to make your solar system more efficient? Tips:you can make the string based on the electric current of the solar panel.
Till now,we have discussed how to choose the solar panels in three parts,I hope all of you can get the good quality panels for your solar system.
We will be happy to get feedback or questions from you, you can send email to：sales@pv-system.net