Publish Time: 2023-04-27 Origin: Site
Photovoltaic cables are one of the most important accessories for solar power generation. Moreover, there are many steps involved in wiring, among which choosing the correct photovoltaic cable size is more important; what size should the suitable photovoltaic cable be? You may worry about this. Selecting the proper photovoltaic cable size for your photovoltaic panel system can facilitate operational and usage safety.
Generally speaking, if the size of the photovoltaic cable is too small, some accidents may occur, for example, the temperature of the wire and cable is too high, which may cause a fire. Therefore, here we will discuss some questions about how to choose the size of photovoltaic cables.
The standardized scale for PV cable sizes is called American Wire Gauge or AWG. There are different sizes and different wire gauge sizes. The difference in size will directly affect the laying operation.
In general, the higher the gauge number, the greater the resistance of the PV cable and the lower the current it can safely handle.
In addition, different usage purposes require different wire diameters. For example, the photovoltaic cables used to connect to the batt
ery pack may require a different size than the wires used to connect to the charger controller.
It can vary depending on the type of solar system you have. Residential solar systems and commercial systems require different wire sizes.
For those who don't know the size of photovoltaic cables, it is confusing to hear the size of photovoltaic cables AWG, but it is simple and easy to understand. In fact, it refers to the size of wire required to connect the size of the components of the solar panel system.
As we all know, there are many components in a solar panel system, and they include solar panels, batteries, charge controllers, and inverters. To build a complete solar system, you need to use photovoltaic cables to connect them together to form a circuit. Wires carry electrical current, and electrical current can flow from or to certain components through the wires.
Photovoltaic cable size refers to the diameter and length of the wire. If the diameter of the wire is large, its resistance will be small, and the current will be smooth and safe, otherwise, the resistance will be large and hinder the flow. Also, if the length is too long, the resistance will rise, which may make it difficult for current to flow.
The average scale of PV cable sizes is named American Wire Gauge (AWG). You can search for PV cable sizes online for normal residential usage and their corresponding ampere ratings. Or let's take some of them as examples.
3/0 Spec: 200 Amps
1/0 Size: 150 Amps
3 Specs: 100 Amps
6 gauge: 55 amps
8 gauge: 40 amps
10 gauge: 30 amps (suitable for dryers, appliances, and air conditioners)
12 gauge: 20 amps (suitable for electrical, laundry and bathroom circuits)
14 gauge: 15 amps (for general lighting and receptacle circuits)
Before doing the calculations for the various parts of a solar system, there are a few terms you should understand.
Voltage: Voltage refers to the potential difference, which refers to the potential difference between the two ends of a circuit. It is denoted as "V" in the equation and is evaluated in volts (V). Voltage drop index: When the wire size is too small, the voltage will decrease, resulting in wire voltage drop and power loss. This reduced index is called the pressure drop index. Current: Current is the current that flows in a circuit, like water in a tube. We use "I" to denote this as a formula term. Current refers to the rate of flow of electric charge and is evaluated in amperes.
The PV cable size for a solar panel system is determined by the partial load current, the voltage, the length of the PV cable carrying the current, and the voltage drop exponent.
1. For connection wires of commercial solar panels over 50 watts, 10 gauge wire is required. Based on the dimensions this gives, 10 watts corresponds to 30 amps. This means that the photovoltaic cables can handle up to 30 amps per solar panel.
2. If multiple panels are connected together in parallel, the circuit needs a larger gauge to form a combiner group. Depending on the number of solar panels you are wiring, you can choose the size of the wire.
3. Usually, in order to ensure and work safely and smoothly, you can choose 3, 6 or 8 photovoltaic cables to connect the solar panel to the charge controller and other components.
4. For the connection between the solar controller and the battery pack, it is said that the photovoltaic cable of the same specification as that used by the parallel circuit combiner can be selected.
5. But there will be an exception when the combiner bank of the solar panel works at a voltage higher than that of the charger controller. You should choose a larger PV cable size. For example, "If the charge controller works with a 12V or 24V battery, and the solar panel works at 48V or higher, an abnormal situation will occur. The charge controller transformer can reduce the voltage accordingly, and the charge controller to the battery. The current will increase".
6. For PV cables between battery packs, the situation is different. If your solar system requires more than one battery, the battery pack will contain at least two batteries. So you need to choose the right size of wires to connect them and other parts.
7. Since the battery pack will be connected to the inverter at the same time, the current of this line should be able to handle the needs of inverter and charging. Therefore, the current in the battery pack wires is likely to be the highest.
8. In this case, you can choose 1/0 or 3/0 gauge wire, which can provide current from 150 amps to 200 amps.
9. For the connection from the inverter to multiple devices, you can choose 12 or 14 PV cables. They require relatively little current.
We know from the previous discussion that if the wire size is undersized, the voltage drop will be severe and there will be more power loss. In addition to this, the length of the wire can also affect the performance of the solar system.
Since the length of the wire can increase the resistance of the wire and cause an excessive voltage drop, you should do some calculations on the wire you need.
Additionally, the PV cable between the solar panel array and the charge controller is the longest of all component connections. Therefore, you need to choose a photovoltaic cable of appropriate size and length to ensure safe and smooth current flow.
In general, for a solar system to function well and be safe, it should be wired correctly. In order to connect them perfectly, you should first choose the correct wire size. Throughout the selection process, you'll need to do some calculations and research.
Since our establishment in 2013, XSD Cable has been one of the professional manufacturer in the field of wire and cable.