ABB | S203U-K20
S 200 U miniature circuit breaker, 3 poles, 480Y/277 V AC, tripping characteristic K, 20 AMP

MFR PART #  S203U-K20
PART #  517829
Available in 1 Each increments
Minimum 1 Each
Call for Availability


System pro M compact S200U miniature circuit breakers are current limiting. They have two different tripping mechanisms, the delayed thermal tripping mechanism for overload protection and the electromechanic tripping mechanism for short circuit protection.


For Commercial And Industrial Purpose. All MCBs of the product range S200U comply with IEC/EN 609 47-2, UL489 and CSA 22.2 No. 5, allowing the use for commercial and industrial applications.


  • Current limiting
  • Fast breaking time (2.5 - 3.5 msec)
  • Unique bus connection system
  • Wide range of accessories
  • Available with variable depth handle mechanism
  • Optional Z curve for SCR protection
  • CE certified and marked
  • DIN rail or front panel mng
  • Finger safe terminals
  • Multi-function terminals
  • Suitable for reverse feed
  • 480Y/277 V AC and 500V DC versions
  • UL489 - branch circuit protective device. UL file #E212323

Specification Description

Voltage Rating: 400 - 440 V AC
Amperage Rating: 20 A
Frequency Rating: 50/60 Hz
Trip Type: Thermal Magnetic
Trip Range: Magnetic: 160 - 240 A, Thermal: 21 A
Interrupt Rating: 10 kA
Number Of Poles: 3
Enclosure: IP20, IP40 With Cover
Actuator: Insn Group II, Black, Sealable, I/O Marking
Material: Insulation Group I, RAL 7035
Length: 71 mm
Width: 52.5 mm
Height: 92 mm
Environmental Conditions: Storage Temperature: -40 To 70 DEG C
Connecting Capacity: Conductor: 18 - 4 AWG, Busbar: 18 - 8 AWGhtening Torque: 25 in-lb
Recommended Screw Driver: Pozidriv 2
Mounting: DIN Rail: TH35-15 (35 mm Length X 15 mm Width), TH35-7.5 (35 mm Length X 7.5 mm Width)
Energy Limiting Class: 3
Insulation Voltage: Phase To Ground: 250 V AC, Phase To Phase: 500 AC
Tripping Characteristic: K
Impulse Withstand Voltage: 4 kV
Contact Position Indication: ON/OFF
Pollution Degree: 2
Overvoltage Category: III
Dielectric Test Voltage: 2 kV At 50/60 Hz For 1 min
Endurance: Electrical And Mechanical: 20000 Cycles

Tech Info

UL 489 Listed, CSA 22.2 No. 5, CE Certified, IEC/EN 60947-2 Approved, RoHS Compliant


UNSPSC Code 39121601

Spec Sheet

Spec Sheet

Shipping and Fulfillment Policy

When you order products from, the order is processed within one to two business days. Orders received during non-business days are processed on the next business day.

You have several shipping options for parcel shipping: standard ground 5 to 7 business days, 2 to 3 business days, or next business day. orders ship to addresses within the United States. orders do not currently ship to addresses outside the United States or military/government APO/FPO locations. We are also not able to ship to Post Office Box addresses. If you wish to ship to an address outside the United States or a military/government location, please contact your local Anixter sales representative to discuss your options.

In addition, offers Less-Than-A-Truckload “LTL” option for products that cannot be shipped via parcel shipping. For products that will be shipped via LTL, you will be provided with a set of Accessorials to select from to provide Anixter with additional shipping considerations, such as residential delivery, inside delivery, liftgate or limited access.

  • Residential Delivery - A residential delivery charge applies to shipments to a home or private residence, including locations where a business is operated from a home, or to any shipment in which the shipper has designated the delivery address as a residence.
  • Inside Delivery - When requested, freight carrier unloads shipments from or to areas that are not next to the trailer, such as shopping malls or office buildings. An elevator must be available to provide service to floors above or below the trailer.
  • Liftgate - Freight carrier provides liftgate service, if needed, to load and unload a shipment when loading/unloading docks are not available.
  • Limited Access Locations - A limited access location is a site where pickup or delivery is restricted or limited.

Shipping charges are calculated based on the shipping option you select, and is prepaid by you at the time of shipment.