Siemens | QJ3B100A02 | Circuit Breaker | 100A | 3-Pole | 240V

Siemens QJ3B100A02 Circuit Breaker — a precise, dependable protection solution engineered for demanding 3‑phase electrical systems. With a 100A rating and 240V operational capability, this 3‑pole breaker is designed for maintenance, retrofit, and replacement scenarios where exact specifications matter. Rely on Siemens engineering to safeguard your equipment while keeping your panel aligned with its original protection strategy.

Key specifications

• Amperage: 100A
• Poles: 3‑Pole
• Voltage: 240V
• Part number: QJ3B100A02

Why this matters

In any 3‑phase installation, matching protection devices to the system’s exact ratings is crucial for reliable operation and safety. The QJ3B100A02 is a purpose‑built Siemens component that aligns with the manufacturer’s protection philosophy, helping your electrical infrastructure respond predictably to overloads and faults. Its 3‑pole design supports three‑phase circuits, ensuring balanced protection across all phases and reducing the risk of nuisance trips or mismatches in your panel.

Ideal use cases

• Maintenance: Replace a worn or failed breaker to restore original protection without reconfiguring the panel.
• Retrofit: Upgrade or convert existing 3‑phase installations to maintain proper amperage and trip characteristics.
• Replacement: Use as a drop‑in substitute in Siemens‑compatible panels and assemblies that require the QJ3B100A02 reference.
• Spare part for service fleets: Keep a compatible Siemens 100A, 3‑pole unit on hand to minimize downtime during field service.

Compatibility and buying tips

To ensure a seamless fit, rely on the part number QJ3B100A02 as the primary reference for compatibility. Always confirm fit and ratings before ordering by cross‑checking with your panel model and the surrounding protection scheme. Using the exact Siemens part helps avoid compatibility gaps and ensures the intended trip characteristics and coordination with other protective devices in your system.

What to expect in operation

When integrated into a suitable 240V, 3‑phase panel, this circuit breaker provides dependable overcurrent protection aligned with Siemens specifications. With exact amperage and pole configuration, it supports safe shutdown of motor loads and other 3‑phase equipment, preserving equipment life and reducing the risk of electrical faults cascading through the circuit.