What the TMF rating means for fit
The XT1HU3060AAA000XXX: The TMF trip unit provides fixed thermal-magnetic protection — the thermal element handles overloads (inverse-time curve), the magnetic element clears short-circuits instantaneously. This is the same trip technology used across the XT1H line, so replacement and spare-parts commonality with other XT1H breakers in the panel is straightforward.
