Siemens HED43B090L - 90 A, 480 V, 3-Pole Bolt-On Circuit Breaker | AmpState

Meet the Siemens HED43B090L—a 90A, 480V, 3-pole bolt-on molded case circuit breaker designed for reliable branch circuit protection in panelboards and loadcenters. Built to perform in residential, commercial, and light industrial environments, this unit delivers precise, durable protection where it matters most.

• Secure bolt-on mounting for a rigid, vibration-resistant bus connection that maintains high-quality electrical contact even in demanding installations.
• Thermal-magnetic trip unit delivers stable, repeatable protective action against overcurrent and short circuits, reducing nuisance trips and helping ensure coordination with upstream devices.
• OEM-ready compatibility engineered to align with matching Siemens loadcenters and panelboards for straightforward, plug-and-play installation.
• 3-pole design for 3-phase systems ideal for 480V, three-phase feeders and protection of commercial and light industrial circuits.
• Rugged construction built to withstand vibration and environmental stresses typical of panel installations, delivering long-term reliability.

Why this breaker stands out in a world of generic protection devices, the HED43B090L combines precise thermal-magnetic tripping with a solid bolt-on mount, ensuring secure connections and predictable trip behavior under load. This means fewer unexpected outages and more consistent protection for your electrical gear.

Key specifications at a glance

• Manufacturer: Siemens
• Part number: HED43B090L
• Type: Thermal-magnetic molded case circuit breaker
• Amperage rating: 90A
• Voltage rating: 480V
• Number of poles: 3
• Mounting style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Ideal use scenarios

The Siemens HED43B090L is well-suited for:

• New installations in commercial panelboards and industrial loadcenters that require 480V three-phase protection.
• Upgrades or replacements in existing Siemens systems where a high-reliability, bolt-on MCCB is preferred.
• Applications demanding robust vibration resistance and durable connections in demanding electrical environments.

Practical considerations and installation tips

To maximize performance, ensure the bolt-on terminals are torqued to the manufacturer's specifications and that the breaker is seated firmly in the panelboard bus before applying voltage. This unit is designed to coordinate with Siemens OEM components, so using it within a matched Siemens system helps maintain consistent trip characteristics and protective coordination.

For professionals planning a 3-phase 480V feeder or upgrading protection in a panelboard, the HED43B090L provides a dependable, field-proven solution that combines secure mounting, precise protection, and OEM compatibility—delivering clear, real-world advantages for reliable electrical safety and system uptime.