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ABB S803S-B40 — 3-Pole MCB (DIN Rail)

S803S-B40 40A 3-Pole Trip Curve B MCB, 50 kA

MPNS803S-B40

ABB S803S-B40, 40 A, 3-pole, Trip Curve B miniature circuit breaker, 50 kA interrupting capacity, DIN rail mount.

ABB S803S-B40 datasheet (PDF)
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

S803S-B40 — Identification
ParameterValue
Number of poles3
S803S-B40 — Electrical
ParameterValue
Voltage (AC)230
Current (A)40
S803S-B40 — Protection
ParameterValue
Interrupting rating (AC)50 kA
S803S-B40 — Mechanical
ParameterValue
Mounting typeDIN Rail
S803S-B40 — Other specifications
ParameterValue
TypeTrip Curve B

Product details

The ABB S803S-B40 is a 40 A, 3-pole miniature circuit breaker (MCB) with a Trip Curve B characteristic. The 50 kA interrupting rating at 400 V AC means it can safely clear a bolted fault up to that level without welding its contacts or rupturing the case — critical for high-fault-capacity panels where a standard 10 kA MCB would fail. Curve B trips between 3× and 5× rated current (120–200 A), so it's sized for resistive or lightly inductive loads where inrush is low; it will nuisance-trip on motor or transformer starts that draw higher peaks.

This is a current-production part.

Panel integration

Rated 400/690 V AC, 375 V DC, 50/60 Hz — suitable for three-phase distribution panels in commercial or light industrial switchgear.

Frequently asked questions

Where can I buy S803S-B40 and how do I get a price?

Submit an RFQ for the S803S-B40. Availability and current pricing are confirmed at quote time through independent distribution channels.

What is S803S-B40's interrupting rating?

The S803S-B40 has a 50 kA interrupting capacity at 400 V AC, which means it can safely clear high fault currents without damage to itself or the panel.

What loads is Trip Curve B suitable for?

Curve B trips at 3× to 5× rated current, so it is best for resistive loads (heaters, lighting) or low-inrush circuits. It is not recommended for motor or transformer starting without coordination study.

MPN
S803S-B40