Square D · Electronic Components
QO140
CIRCUIT BREAKER, THERMAL MAG, 1P, 40A
Part NumberQO140
ManufacturerSquare D
AvailabilityAvailable to order — request a quote
Specifications
NSN5925-01-609-2608 (NSN)
Federal Item NameCIRCUIT BREAKER
Terminals2 BUS BAR
Body StyleSINGLE POLE TYPE
Reset MethodMANUAL
Circuit Protection TypeOVERVOLTAGE SINGLE LOCATION
Maximum Continuous Load Current Ra40.0 AMPERES AC SINGLE LOCATION
Operating Voltage Type And Rating120.0 AC AND 240.0 AC SINGLE LOCATION
Body Length2.910 INCHES NOMINAL
Pole Quantity1
Body Width0.750 INCHES NOMINAL
Body Height3.120 INCHES NOMINAL
Federal Supply Class5925 — Circuit Breakers
Terminal Type And Quantity2 BUS BAR
Trip Release CharacteristicINSTANTANEOUS SINGLE LOCATION
ESD/EMICode A — ESD/EMI sensitive item
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 QO140 available?
We can source QO140 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 QO140 by Square D obsolete or end-of-life?
We specialize in obsolete, end-of-life, and discontinued components. If QO140 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 QO140?
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 QO140?
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.