The functions of DC MCB and AC MCB are the same. They both protect electrical appliances and other load equipment from overload and short-circuit problems, and protect the circuit safety. but the usage scenarios of AC MCB and DC MCB are different.
It generally depends on whether the voltage used is alternating current states or direct current states. Most of DC MCB uses some direct current systems like new energy, solar PV, etc. The voltage states of DC MCB is generally from DC 12V-1000V.
The difference between AC MCB and DC MCB by only physical parameters, the AC MCB has labels of the terminals as LOAD and LINE terminals whereas the DC MCB will have positive (+) or negative (-) sign on its terminal.
How to connect DC MCB correctly?
Due to the DC MCB has a marking of ‘+’ and ‘-’ symbol only, it is often easy to connect incorrectly. If the DC miniature circuit breaker is connected or wired incorrectly, there are possibilities of problems occurring.
In case of overload or short circuit, the MCB will not be able to cut the current and put out the arc, this may lead to the breaker burning out.
Therefore, DC MCB has a marking of ‘+’ and ‘-’ symbols, still need to mark the circuit direction and wiring diagrams, as shown below:
According to the wiring diagram, 2P DC MCB has two wiring methods, one is the top is connected to the positive and negative poles, another method is the bottom is connected to the positive and negative poles as the marking of ‘+’ and ‘-’. For 4P 1000V DC MCB has Three wiring methods, according to different usage states, to choose the corresponding wiring diagram to connect the wiring.
The solar power system, also photovoltaic (PV) system, It is a kind of energy convert sunlight into electricity for human daily use, it consists of one or more solar panels and inverters and other electrical devices and mechanical hardware that uses solar power output from direct current to alternating current to generate electricity.
The solar power systems range from small rooftops or portable systems, building-integrated systems to large utility-scale power plants, the size of solar power system can vary greatly from a few to several tens of kilowatts.
The light radiation from the sun falls on the solar panel and generates a certain direct current through the process of photovoltaic effect.
Each individual solar panel generates less energy, but can be connected with other solar panels in parallel or in series to generate more energy as a solar array.
How does solar power system work?
The electricity generated by solar panels is in the form of direct current (DC). We can store part of the solar energy through batteries, which can be supplied to some remote areas without power distribution systems.
Through solar DC distribution boxes, power can be distributed to some Electronic equipment that directly uses direct current.
But even though there are many electronic devices that use direct current, including your mobile phone or laptop, they are designed to operate on a utility grid that provides (and requires) alternating current (AC).
Therefore, in order to make solar power for our daily use, we need to use an inverter to convert it from direct current to alternating current. The AC power from the inverter can then be used to power local electrical equipment or sent to the grid for use elsewhere.
How to build a solar combiner box?
General solar combiner box, also pv combiner box according to different power usage configuration requirements, the current ranges from 10A to 800A, and the DC voltage ranges from DC 24V to 1500V.
Commonly used voltages are mainly divided into DC 550V and DC 1000V. For solar combiner boxes with currents above 125A, DC MCCB (moulded case circuit breaker) 125A-800A should be selected. For currents less than 125A, DC MCB (Mini circuit breaker) 6-125A is selected for DC circuit breakers.
In addition to the DC circuit breaker, the Solar combiner box also needs to be equipped with DC Fuse holder, DC SPD (Surge protection device) according to different lightning protection and overload protection requirements.
Our common photovoltaic combiner box is suitable for the inverter’s maximum input power of DC550V/DC1000V.
The TOSSD-PV solar combiner box is made of IP66 high-performance waterproof plastic material, which is fire-resistant, flame-retardant, temperature rise, anti-impact, and anti-ultraviolet. It is very suitable for outdoor Solar power DC system power distribution installation.
TOSSD-PV1-1-T DC 1000V solar combiner box
TOSSD-PV1-1-T DC 1000V solar combiner box
Model
TOSSD-PV1-1
TOSSD-PV2-1
TOSSD-PV4-1
TOSSD-PV4-2
Electrical parameters
System maximum DC voltage
550
1000
550
1000
550
1000
550
1000
Maximum input current per channel
20A
20A
20A
20A
Maximum number of input channels
1
2
4
4
Maximum output switching current
16A/20A
20A/32A
50A/63A
20A/32A
Number of inverter MPPT
1
1
1
2
Number of output
1
1
1
2
Surge lightning protection
Class
T2
T2
T2
T2
Nominal discharge current
20kA
20kA
20kA
20kA
Maximum discharge current
40kA
40kA
40kA
40kA
Voltage protection level
2.8kV
3.8kV
2.8kV
3.8kV
2.8kV
3.8kV
2.8kV
3.8kV
Maximum continuous working voltage
630V
1050V
630V
1050V
630V
1050V
630V
1050V
Pole
2P
3P
2P
3P
2P
3P
2P
3P
Structural features
Plug-in module
Plug-in module
Plug-in module
Plug-in module
system
Protection level
IP66
Output switch
DC circuit breaker (standard) / DC rotary isolating switch (optional)