Part 1:Relevant standards and specifications for cable selection
1. DL/T5044-2004 People’s Republic of China Electric Power Industry Standard
2. GB50217 Power Engineering Cable Design Code
Part 2:Main technical requirements
1. Two-core cables should be used for the DC power supply loop, and single-core cables can be used when needed.
2. Polyvinyl chloride insulated cables are not suitable for high temperature above 100℃ or low temperature below -20℃.
3. When laying cables directly, steel tape armored cables should be used when the cables are under heavy pressure or are in danger of mechanical damage.
4. The temperature of the cable core under the maximum working current shall not exceed the service life of the cable. 5. Determine the ambient temperature for the continuous allowable current carrying capacity of the cable. If the cable is laid in the air or in the cable trench, the highest temperature of the hottest month should be used. average value.
Part 3. The selection of cable path should meet the following requirements
1. Avoid the cables suffering from mechanical external force, overheating, corrosion and other hazards.
2. Make the cable shorter when meeting safety requirements.
3. Easy to install and maintain.
4. Avoid the place to be excavated and the cable shall meet the requirements of the allowable bending radius of the cable in any way of laying and all path conditions of the cable.
Part4. Cable types, characteristics and laying methods of photovoltaic power generation system
1. Special photovoltaic cables
The cables from the string to the combiner box generally use photovoltaic special PV cables PV1-F1*4mm2. The photovoltaic cable has a simple structure, and the polyolefin insulation material it uses has excellent heat resistance, cold resistance, oil resistance, and ultraviolet resistance. It can be used under harsh environmental conditions and has a certain mechanical strength.
2. Power cable
1) Steel tape armored cable flame-retardant cross-linked cable ZRC-YJV22
Widely used: connecting cables from combiner boxes to DC cabinets, DC cabinets to inverters, inverters to transformers, transformers to power distribution devices, and power distribution devices to power grids.
2) Power cable NH-VV
NH-VV copper core PVC insulated PVC sheathed fire-resistant power cable.
3. Control cable
ZRC-KVVP copper core PVC insulated PVC sheathed braided shielded control cable. It is suitable for control, monitoring circuit and protection circuit of AC rated voltage 450/750V and below.
4. Communication cable
1) DJYVRP2-22 polyethylene insulated PVC sheathed copper wire braided shielded armored computer special soft cable, suitable for electronic computers and automation connecting cables with high anti-interference requirements for rated voltages of 500V and below.
2) RVVP copper core PVC insulated PVC sheathed insulated and shielded flexible cable RVVP, also known as electrical connection anti-interference flexible cable, is suitable for alarm, security and other communication cables that require interference prevention and safe and efficient data transmission.
5. RF cable
Solid PE insulated PVC sheathed radio frequency coaxial cable SYV.