UL 458

Power Converters/Inverters and Power Converter/Inverter Systems for Land Vehicles and Marine Crafts<br. ul 458
1 Scope

1.1 These requirements cover fixed and stationary power converters, power-converter systems, and accessories having a rated nominal input of 120, 120/240, or 240 V, alternating current and a nominal output of 24 V or less, direct current. These converters are intended for use within land vehicles where not directly exposed to outdoor conditions, and are intended to be employed in accordance with the National Electrical Code, NFPA 70.

1.2 These requirements also cover fixed, stationary and portable power inverters and power-inverter systems having a dc input and a 120 or 240 V ac output. These inverters are intended for use within land vehicles where not directly exposed to outdoor conditions, and are intended to be employed in accordance with the National Electrical Code, NFPA 70.

1.3 These requirements also cover converters/inverters that are additionally intended to charge batteries.

1.4 Power converters covered by Part i of this standard are intended for connection to established 15- and 20-A branch circuits within a recreational vehicle.

1.5 Power-inverters covered by Part i of this standard are intended for connection to a 12- or 24-V dc battery supply.

1.6 Converters and inverters incorporating provisions for the connection of less than three line-voltage branch circuits are investigated under the requirements in Part i of this standard.

1.7 A power-converter or power-inverter system is intended for direct connection to a power-supply assembly. A system for connection of three or less line-voltage branch circuits, not including the main disconnect, may optionally be evaluated in accordance with the requirements in Part ii of this standard, or with the applicable requirements for a Class CTL panelboard in the Standard for Panelboards, UL 67. Power converter systems and power inverter systems also employ circuitry as described in 1.4 and 1.5.

1.8 A power-converter or power-inverter system provided with more than three line-voltage branch circuits, not including the main disconnect, is investigated to the applicable requirements for a Class CTL panelboard in the Standard for Panelboards, UL 67.

1.9 Converters and inverters incorporating provisions for the connection of more than three line-voltage branch circuits are judged under the requirements in Part i of this standard and the applicable requirements for a Class CTL panelboard in accordance with the Standard for Panelboards, UL 67.

1.10 Each pole of a multiple-pole circuit breaker is a separate circuit.