The Siemens JK3B100 is a 3-pole, 100A molded case circuit breaker designed for commercial power distribution. Built with a rugged JK frame, it provides dependable overcurrent protection. This legacy breaker mounts into Siemens P4 and P5 panelboards, plus older ITE CDP enclosures. It serves as an exact replacement for aging systems and is superseded by the JXD63B100. Rated for 22 kAIC at 480VAC, it features an interchangeable trip unit and adjustable magnetic settings.
Which panelboards are compatible with the JK3B100 circuit breaker?
This bolt-on breaker is designed for use in Siemens P4 and P5 panelboards, as well as legacy ITE CDP panelboards and switchboards.
What wire sizes are accepted by the lugs on this breaker?
The included lugs accept both copper and aluminum conductors ranging from 4 AWG to 300 kcmil.
How does the trip adjustability work on the JK3B100?
This thermal magnetic breaker features a fixed thermal element for 100A overload protection and an adjustable magnetic element, allowing you to fine-tune the instantaneous short-circuit trip threshold.
Can the JK3B100 be used in DC applications?
Yes, this breaker is rated for use in DC systems up to 250VDC, where it provides a 10kA interrupting capacity.
Is there a modern replacement for the legacy JK3B100 breaker?
Yes, the JK3B100 is a legacy JK frame breaker that has been superseded by the JXD63B100 for modern applications, though the JK3B100 remains an exact fit for aging systems.
What safety precautions should be taken before installing this breaker?
Always ensure the panelboard or switchboard is completely de-energized and follow proper lockout/tagout procedures before bolting the breaker to the bus.
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