ul-1066.4Low-Voltage AC and DC Power Circuit Breakers Used in Enclosures
UL 1066
1 Scope
1.1 These requirements cover low-voltage ac power circuit breakers as follows:
a) Stationary-mounted or drawout-mounted types,
b) 2-pole, 3-pole, and 4-pole constructions,
c) Manually operated or power operated, and
d) With or without electromechanical or solid-state type trip device.
1.1 revised effective April 13, 20171.2 These requirements apply to drawout-mounted type low-voltage ac integrally fused power circuit breakers, consisting of low-voltage ac power circuit breakers with integral current limiters or fuses.
1.2 revised effective April 13, 20171.3 These requirements apply to low-voltage ac fuse draw-outs consisting of current limiters or fuses in a drawout assembly intended to be connected in series with a low-voltage ac power circuit breaker to form a fused circuit breaker.
1.3 revised effective April 13, 20171.4 These requirements apply to general purpose type low-voltage dc power circuit breakers.
1.4 revised effective April 13, 20171.5 These requirements cover equipment intended for use in ordinary locations in accordance with the National Electrical Code, ANSI/NFPA 70.
1.5 revised effective April 13, 20171.6 These requirements are intended to supplement and be used in conjunction with the:
a) Standard for Low-Voltage AC Power Circuit Breakers Used In Enclosures, IEEE C37.13,
b) Standard for Low-Voltage DC Power Circuit Breakers Used In Enclosures, IEEE C37.14,
c) Standard for Metal-Enclosed Low-Voltage Power Circuit-Breaker Switchgear, IEEE C37.20.1,
d) Test Procedures for Switchgear - Low-Voltage AC Power Circuit Breakers Used In Enclosures, ANSI C37.50, and
e) Conformance Test Procedures for Switchgear - Metal-Enclosed Low-Voltage AC Power Circuit Breaker Switchgear Assemblies, ANSI C37.51.
1.6 revised effective April 13, 20171.7 These requirements cover equipment rated 1000 V or less nominal, 1058 V maximum ac and 1500 V maximum dc.
1.8 This Standard does not apply to molded-case circuit breakers.
1.8 revised effective April 13, 20171.9 These circuit breakers are intended for installation in circuit breaker enclosures, switchboards (switchgear), panelboards, and the like. Drawout-mounted devices are intended for use with specific adapters or receiving equipment. The acceptability of the combination of a circuit breaker with respect to any overall enclosure will be determined when the complete product is considered.
1.9 revised effective April 13, 2017