Some considerations for the use of fuses in photovoltaic arrays

Some considerations for the use of fuses in photovoltaic arrays

1. Selection requirements for photovoltaic fuses

According to the relevant provisions of IEC 60269-6:2010 and NFPA 70, the fuses of photovoltaic systems must have certain rated current and voltage values to ensure that they play a role in the protection of photovoltaic strings, photovoltaic sub-arrays and photovoltaic arrays. IEC 60269-6 clearly stipulates the specific fuse design requirements for photovoltaic systems, such as rated voltage, circuit breaking capacity and rated current range.

For example, for photovoltaic protection in 1500V DC systems, Zhejiang Galaxy Fuse Co., Ltd.'s YRPV-160 1500VDC Solar Photovoltaic Fuse Link provides rated current options from 40A to 160A, and the appropriate current value can be selected according to the specific application scenario (such as photovoltaic combiner box, photovoltaic inverter). According to IEC and NFPA standards, the rated current of PV fuses should be within the short-circuit current range of PV cell strings or sub-arrays, generally 1.4ISC-MOD to 2.4ISC-MOD.

2. Installation requirements for PV fuses

The fuses in the PV system should be selected and installed according to the actual installation location and protection requirements. Both IEC 60269-6 and NFPA 70 have requirements for the installation location of PV fuses. For example, the fuse should be installed at the location where the PV string conductor is connected to the PV sub-array or PV array conductor, and should be installed at both the positive and negative positions. In addition, at the connection between the PV sub-array and the PV array, the rated current of the fuse should be in the range of 1.25ISC-ARRAY to 2.4ISC-ARRAY, where ISC-ARRAY is the short-circuit current of the PV array under standard test conditions.

In some large photovoltaic power generation systems, the YRPV-250D 1500VDC Solar Photovoltaic Fuse Link (rated current ranging from 80A to 250A) can provide protection for higher current systems. This fuse is particularly suitable for the protection of large photovoltaic combination boxes, photovoltaic arrays and photovoltaic inverter DC inputs.

3. High voltage and high current protection

High voltage and high current protection in photovoltaic systems is particularly important. Especially in 1500VDC photovoltaic systems, the YRPV-160 1500VDC Solar Photovoltaic Fuse Link and YRPV-250D 1500VDC Solar Photovoltaic Fuse Link adopt NH0 and NH1XL standardized sizes, which can effectively withstand high voltage and current working conditions and provide long-term and stable protection for photovoltaic systems.

According to the requirements of IEC 60269-6, the design of the fuse needs to take into account that the short-circuit current of the photovoltaic panel may exceed its nominal value, especially when the photovoltaic panel is in the initial operation. During design, the rated current of the fuse should be calculated according to the ISC-MOD value provided by the PV panel manufacturer and the operating temperature of the system to ensure that it can cut off the current in time when a fault occurs in the PV system to prevent equipment damage.

4. Overcurrent protection and maintenance

In order to ensure the safe and efficient operation of the PV system, the selection of fuses must not only meet the short-circuit current protection requirements, but also be able to cope with the overcurrent risks in long-term use. In some cases, when the rated current of the fuse is close to its lower limit, auxiliary protection devices such as overcurrent protection relays are required, especially when the system current fluctuates greatly.

For example, the YRPV-160 1500VDC Solar Photovoltaic Fuse Link and YRPV-250D 1500VDC Solar Photovoltaic Fuse Link can provide flexible current protection solutions according to different PV array configurations, thereby ensuring that the system can be effectively protected even in long-term use.

5. Product certification and standard compliance

When purchasing PV fuses, product certification and compliance with international standards are crucial. For example, the YRPV-160 1500VDC Solar Photovoltaic Fuse Link and YRPV-250D 1500VDC Solar Photovoltaic Fuse Link comply with the IEC 60269-6 standard, providing protection functions that meet global requirements. With these certifications, photovoltaic projects can ensure the quality and reliability of products, providing stronger protection for system operation.

Conclusion

The correct selection and installation of photovoltaic fuses are the key to ensuring the safe and stable operation of photovoltaic systems. Whether it is the protection of photovoltaic strings, photovoltaic sub-arrays or the entire photovoltaic array, it needs to be designed and implemented in accordance with international standards such as IEC and NFPA. YRPV series photovoltaic fuses, such as YRPV-160 1500VDC Solar Photovoltaic Fuse Link and YRPV-250D 1500VDC Solar Photovoltaic Fuse Link, can not only meet the protection needs of different application scenarios, but also effectively cope with the challenges of high voltage and high current, providing long-term and stable protection for photovoltaic power generation systems.