The TMF designation means the thermal and magnetic pickup settings are factory-fixed — no field-adjustable dials for the overload or short-circuit thresholds. This is a common choice for dedicated motor or feeder circuits where coordination studies have already locked in the trip curve, and you want to avoid an accidental setting change during maintenance.
ABB XT4LU3250AFF000XXX XT4L 250 A TMF Molded Case Circuit Br
MPNXT4LU3250AFF000XXX
ABB XT4LU3250AFF000XXX, XT4L series, 250 A TMF molded case circuit breaker (MCCB), current lifecycle stage.
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Aug 2026
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Frequently asked questions
Where can I buy the XT4LU3250AFF000XXX and get a price?
This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm price and lead time.
What does the 'TMF' in the XT4LU3250AFF000XXX description mean?
TMF stands for thermal-magnetic fixed trip unit. The overload (thermal) and short-circuit (magnetic) trip settings are factory-set and not field-adjustable. This contrasts with an adjustable electronic trip unit, which allows dialing in different pickup currents and time delays.
MPN
XT4LU3250AFF000XXX