In 2019, we launched the 200 and 400 amp Compact Circuit Protector with CUBEFuse, but quickly pulled the 400 amp version back and didn't relaunch it until just this October. Our Power of space sample kits in the field still contain the original 400 amp CCP, and we've mentioned that the official version has changed slightly. You asked what specifically changed and why. Here is the response from Bussmann:

The 400 A Compact Circuit Protector with Class CF CUBEFuse was originally launched in January of 2019 but, while it was UL Listed, our engineering team knew we could design a product that mitigated heat better and was easier to operate. Several design changes were implemented and we launched the official 400 A CCP in October 2021.

There are three key design changes — all of which were made to reduce and mitigate heat better. First, vents were added above the switching mechanism (causing the front rotary mechanism cap to become smaller). Second, the fuse clips were redesigned and, in doing so, the new spring system resulted in less force needed for insertion and extraction of the CUBEFuse. Finally, the switching mechanism was redesigned and, as a result, has an improved electrical connection and is easier to operate. While the fuse clips and switching mechanism look the same as the 2019 version, both are new systems internally.

Dimensionally, the 400 A CCP is slightly taller (10.35 inches versus 10.1 inches) and slightly deeper (5.86 inches versus 5.2 inches) than the one launched in 2019. The width of the CCP (without side mech) remains the same at 5.1 inches.

Bussmann series fuses play a major role in industrial or commercial facilities by providing reliable, maximum protection to power systems. Their physical size or rejection features prevent replacing a fuse with one from another fuse class. This helps ensure the correct replacement fuse is always installed and the voltage and interrupting ratings remain the same.