
1. Selection of inverter fuse and disconnector
The function of the disconnector is to disconnect the circuit in case of emergency, in which traveling disconnecting ability is mainly fuse melting, so the selection of the disconnector mainly depends on the fuse.
① First of all, we must understand the power of the inverter is often expressed in watts (W) or volt-ampere (VA), the premise is to ensure that the selection of the inverter is in line with the circuit ② Determine the voltage of the solar system, according to the system’s voltage is often 12V, 24V and 48V ③ According to the current selection of fuses, understand the power of the inverter and the system voltage, according to the following: Power (W) = Voltage (V) * Current (A) calculating the circuit contained in the current Size, for example, 1000W, 12V circuit current of 1000W/12V = 83.3A, the current of the fuse is generally higher than the rated current by 25% to prevent the fuse from randomly breaking, then the fuse should be 83.3A * 1.25 = 104.1A.
For example, 12V
600W 80A
800W 110A
1000W 200A
1500W 300A
2400W to 3000W 400A
24V.
1000W 80A
600W 50A
800W 75A
300W~4000W 300A
48V
3000W~3600W 110A
4000W 200A
5500W 400A
2. Solar inverter cable selection
Inverter cable considerations, inverter cable is mainly connected to the solar inverter in the power supply to transmit DC power of the special wire, select the inverter cable to consider the current size, length and material which cable specifications indicate its size and the power of the inverter and power supply and the distance from the inverter related. Mainly refer to the inverter voltage and power, wire diameter (AWG)
12 volts
600W 2AWG
800W 2AWG
1000W 2/0AWG
1500W to 3000W 4/0AWG
24 Volt:
600W 8AWG
800W 4AWG
1000W 2AWG
1500W~2500W 2/0AWG
3000W to 4000W 4/0AWG
48V.
3000W~4000W 2/0AWG
5500W 4/0AWG
In order to prevent the cable from being too long resulting in power loss when installing minimize the length and can choose to increase the radius of the cable to reduce the pressure of the current on the cable and reduce the resistance of the cable, the cable wire material is now mainly copper, copper by virtue of excellent electrical conductivity, low resistance and durability is used by the people.
Conclusion
The choice of resistance wire and disconnectors must be about 1.25 times the rated current is too large to lead to the inability to disconnect too small to lead to frequent disconnections, at the same time the choice of inverter cables must take into account the size of the current in the circuit to choose the appropriate wire diameter size.