Key considerations in selection of MC4 connectors in a solar power plant

MC4 connectors are a crucial component in any solar power plant as they connect the solar panels to the cables that carry the power to the inverter. The MC4 connectors have been a popular choice for photovoltaic systems and have been extensively used in the solar industry. In this blog, we will discuss the MC4 connector selection criteria in a solar power plant.

MC4 connectors are a type of DC connectors that are commonly used in the solar industry. They are named MC4 because they are the fourth generation of Multi-Contact connectors. MC4 connectors are known for their high level of safety and reliability, making them a preferred choice for solar power plants. Here are some of the key criteria to consider when selecting MC4 connectors for a solar power plant:

1. Type: MC4 (Y/T/F) or Compatible with Module Connector When selecting MC4 connectors, it is essential to ensure that they are compatible with the module connector. MC4 connectors come in different types, including Y, T, and F types. The type of MC4 connector used will depend on the system’s design and the number of solar panels in the array.
2. Rated Voltage: 1500 V DC The rated voltage of the MC4 connector should be at least 1500V DC. This ensures that the connector can handle the high DC voltages generated by the solar panels.
3. Current Rating: 30 A (or as per design) The current rating of the MC4 connector should be at least 30A. This is because the solar panels generate a high current when exposed to sunlight, and the connectors should be able to handle this current.
4. Cable Cross Section: As per Design Requirement (4 Sqmm/6 Sqmm) The cable cross-section of the MC4 connector should be as per the design requirement. This ensures that the connector can handle the current and voltage levels in the solar power plant.
5. Test Voltage: 6kV (50Hz,1Min) The MC4 connectors should be tested at a voltage of 6kV (50Hz,1Min) to ensure that they can handle the high voltages generated by the solar panels.
6. Rated Impulse Voltage: 16 mV The rated impulse voltage of the MC4 connector should be at least 16 mV. This ensures that the connector can handle the high voltage spikes generated by lightning strikes and other transient events.
7. Contact Resistance: <0.5 mΩ The contact resistance of the MC4 connector should be less than 0.5 mΩ. This ensures that the connector can efficiently transfer power from the solar panels to the cables.
8. Degree of Protection: IP68 The MC4 connector should have a degree of protection of IP68, which means that it is dust-tight and can withstand immersion in water beyond 1 meter.
9. Safety: Class II The MC4 connector should be designed as per Class II safety standards, which ensures that it provides a high level of electrical insulation and protection against electric shock.
10. Fuse: Each Input of the Connector on Positive side is provided with Fuse for protection The MC4 connectors should have a fuse on each input of the connector on the positive side to protect against overcurrent and short circuits.
11. Flammability Rating: UL 94 V-0 The MC4 connector should have a flammability rating of UL 94 V-0, which means that it is highly resistant to fire.
12. Type test for DC Plug Connector- MC4/Y Connector needs to be performed & the manufacturer will submit the reports. The MC4 connector should undergo type testing as per IEC 62852:2014, IEC 62930, IEC 62790