The Siemens 5SL4440-0RC is a 4-pole miniature circuit breaker rated 40 A with Z-characteristic trip curve and a 10 kA breaking capacity. The Z curve is designed for semiconductor and sensitive electronic loads where the inrush is minimal but short-circuit protection must be fast — it trips between 2.5 and 5 times rated current, which is tighter than a B or C curve. That makes it a fit for protecting PLC power supplies, control transformers, or DC-side circuits in a 400 VAC panel where a standard MCB would nuisance-trip on load capacitance.
Siemens 5SL4440-0RC MCB, 40A 4-pole Z-characteristic 10kA
MPN5SL4440-0RC
Siemens 5SL4440-0RC, Miniature Circuit Breaker 40A 4-pole Z characteristic 10kA.
StockContact for availability
MOQ1 pcs
Sourced new & surplus through independent channelsListing updated Jul 2026
Product details
Frequently asked questions
What does the Z characteristic mean on this MCB?
The Z characteristic trips between 2.5 and 5 times rated current, making it suitable for protecting semiconductor circuits and sensitive electronic loads where a standard B or C curve would cause nuisance tripping from capacitive inrush.
Where can I buy the 5SL4440-0RC?
This part is sourced and quoted to order against an RFQ through independent distribution, with availability and current pricing confirmed at quote time.
MPN
5SL4440-0RC