Siemens SN421 Enclosed Switch is a heavy‑duty three‑pole disconnect rated 30 A at 240 V AC for 3‑phase circuits. UL File E4776 lists the SN421 among models approved for use as an enclosed switch and as a service entrance switch, validating its role in feeders and equipment isolation within electrical panels. This enclosed switch provides a compact, durable power‑isolation solution for industrial or commercial panel installations requiring a dedicated disconnect on a 3‑phase feed, with a 30 A rating that suits many 3‑phase applications in electrical distribution systems.
