We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Grey moulded plastic three-pole circuit breaker with front lug terminals and Siemens branding

SIEMENS

SIEMENS ED43B050 Circuit Breaker 50A 3 Pole 480V AC

SKU CH-9VPR-FW0AM

Three-pole molded-case breaker rated 50 A at 480 V AC with 18 kA interrupting capacity and thermal-magnetic trip

  • 50 A thermal-magnetic trip protects three-phase circuits
  • 18 kA interrupting rating at 480 V AC handles high fault currents
  • ED4 frame rated to 125 A fits standard lug-in panelboards
  • Fixed instantaneous trip simplifies coordination with downstream devices
  • Three-pole design switches all phases simultaneously for balanced protection

ED4 Series 50 A Three-Pole Breaker

The Siemens ED43B050 is a molded-case circuit breaker rated at 50 amperes with three poles for 480 V AC systems. It uses a fixed thermal-magnetic trip set at 50 A for both low and high settings and mounts by lug connection inside compatible panelboards. The frame size is 125 A and the interrupting rating reaches 18 kA at 480 V AC.

Replaces Lower-Rated or Single-Pole Protection

This breaker takes the place of devices with lower ampere ratings or fewer poles when a three-phase 50 A circuit requires coordinated overload and short-circuit protection. The jump is warranted when the load demands the full 50 A setting and the panelboard accepts the ED4 frame with lug-in mounting.

Sustained Load Behaviour

Under continuous loading the thermal element responds to prolonged overcurrent while the magnetic element operates instantly on fault currents up to the 18 kA rating. The fixed instantaneous trip does not adjust, so the breaker clears sustained faults without nuisance tripping during normal inrush.

Highlights

  • 50 A thermal-magnetic trip protects three-phase circuits
  • 18 kA interrupting rating at 480 V AC handles high fault currents
  • ED4 frame rated to 125 A fits standard lug-in panelboards
  • Fixed instantaneous trip simplifies coordination with downstream devices
  • Three-pole design switches all phases simultaneously for balanced protection

Specifications

BrandSIEMENS

Questions about this item

Will the 125 A ED4 frame fit in an existing SB switchboard or Sentron panelboard?

The breaker is built for SB switchboards and Sentron panelboards using a lug-in mounting style that matches the bus bars in those enclosures.

How do I install the ED43B050 and what step is often missed?

Mount the 3-pole unit onto the panelboard bus, then torque the load-side lugs to the value printed on the breaker label; skipping the torque step can cause hot spots.

What part will need replacement after a fault trip?

The thermal-magnetic trip unit has fixed 50 A settings and cannot be reset after a short-circuit event, so the entire molded-case breaker must be replaced.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.