UL 4248-19 2021 pdf download – Fuseholders – Part 19: Photovoltaic Fuseholders.
3 Units of Measurement 3.1 The values given in SI (metric) shall be normative. Any other values given shall be for information purposes only. 4 General 4.1 In Canada, general requirements applicable to this Standard are given in CSA C22.2 No. 0, General Requirements – Canadian Electrical Code, Part II. 5 Classification 5.1 Fuseholders for use with photovoltaic (PV) fuses shall have a minimum short-circuit withstand rating of 10 kA and shall be rated 1500 Vdc maximum. 6 Ratings 6.1 Fuseholders for use with photovoltaic (PV) fuses may be rated 1500 Vdc maximum, and the preferred ratings are 600 V, 750 V, 1000 V, 1250 V, and 1500 V. 6.2 Fuseholders for use with photovoltaic (PV) fuses shall have a minimum short-circuit withstand rating of 10 kA. 7 Markings 7.1 Fuseholders for use with photovoltaic (PV) fuses shall be marked in accordance with Part 1. In the United States and Mexico, the French markings are not required. In Canada and the United States, the Spanish markings are not required. 7.2 The information on a fuseholder shall be legible and include the following: a) “Use Photovoltaic (PV) Fuses” or equivalent and « Utiliser des fusibles photovoltaïques » or the equivalent and “Utilizar fusibles fotovoltaicos (PV)” or equivalent; b) “Line” and “Load” for panel mount and in-line fuseholders and « Secteur » et « Charge » and “Línea” y “Carga”; c) “DO NOT OPEN or REMOVE UNDER LOAD” or equivalent and « NE PAS UTILISER SOUS CHARGE » or the equivalent and “NO ABRIR O QUITAR BAJO CARGA” or equivalent (intended for modular design photovoltaic (PV) fuseholders such that the fuse is inserted or removed by use of a carrier); and d) “Do Not Connect or Disconnect under Load” or equivalent and « NE PAS BRANCHER OU DÉBRANCHER SOUS CHARGE » or the equivalent and “No conectar o desconectar bajo carga” or equivalent (intended for photovoltaic (PV) fuseholders that include a wire connector feature). 7.3 PV fuseholders employing an integral, non-user replaceable fuse need not bear the markings specified in 7.2 (a) – (d).
9 Tests 9.1 Verification of temperature rise 9.1.1 If the fuse and fuseholder form an integral device intended to be replaced as a unit, then the actual photovoltaic (PV) fuse, not a dummy fuse, may be used in testing. If the photovoltaic (PV) fuse is used, the applicable temperature limits shall be the limits specified in Table 9.1 plus 20°C (36°F). 9.1.2 The temperatures specified in Table 9.1 are based on an assumed ambient temperature of 25°C (77°F). A test may be conducted at an ambient temperature within the range of 20 – 50°C (68 – 122°F). 9.1.3 If a test is conducted at an ambient temperature other than 25°C (77°F), an observed temperature shall be corrected as described in 9.1.4. No corrected temperature shall exceed the required value specified in Table 9.1. 9.1.4 An observed temperature shall be corrected by addition [if the test ambient temperature is lower than 25° C (77° F)] or subtraction [if the test ambient temperature is higher than 25° C (77° F)] of the difference between 25°C (77°F) and the test ambient temperature. 9.1.5 If a corrected temperature exceeds the required value specified in Table 9.1, at the request of the manufacturer, the test may be repeated at an ambient temperature closer to 25°C (77°F). 9.1.6 The temperature limits shown in Table 9.1 shall not be exceeded.