Square D · Electronic Components
QOB390
MINIATURE CIRCUIT BREAKER 240V 90A
Part NumberQOB390
ManufacturerSquare D
AvailabilityAvailable to order — request a quote
Specifications
NSN5925-01-359-1967 (NSN)
Federal Item NameCIRCUIT BREAKER
MaterialPLASTIC CASE
Terminals6 COMPRESSION
Overall Length3.000 INCHES NOMINAL
Overall Width2.910 INCHES NOMINAL
Overall Height2.250 INCHES NOMINAL
Body StyleRECTANGULAR DIMENSIONAL ENVELOPE
Maximum Interrupting Capacity Curr10000.0 AC ALL LOCATIONS
Circuit Protection TypeOVERCURRENT ALL LOCATIONS
Ultimate Trip Rating Of Continuous125.0 ALL LOCATIONS
Mounting Facility Type And Quantit4 UNTHREADED HOLE(S)
Federal Supply Class5925 — Circuit Breakers
RH Electronics, Inc. — independent stocking distributor since 1982.
Every shipment inspected on receipt · ISO 9001:2015 · ANSI/ESD S20.20 · ERAI member since 1998 · GIDEP participant
Every shipment inspected on receipt · ISO 9001:2015 · ANSI/ESD S20.20 · ERAI member since 1998 · GIDEP participant
Frequently asked
Is QOB390 available?
We can source QOB390 even if it isn't in our active stock list. As an independent distributor we reach inventory outside the franchise channel — including hard-to-find and obsolete parts. Send us a quote request.
Is QOB390 by Square D obsolete or end-of-life?
We specialize in obsolete, end-of-life, and discontinued components. If QOB390 has been discontinued, we can often source remaining stock or qualified alternates. Contact us with your quantity and target date.
How does RH Electronics verify parts like QOB390?
Every incoming shipment is inspected under our ISO 9001:2015 quality system — documentation, markings, and construction checked against known-good references. For deeper analysis, we direct work through accredited independent labs. We've been an ERAI member since 1998 and a GIDEP participant.
Can you find a cross-reference or alternate for QOB390?
Yes. Our team reads part numbers the way they were designed — decoding family, speed, temperature grade, package, and reliability level — to identify acceptable alternates when the exact part isn't available. Submit a quote request and we'll advise.