The 3NJ6920‑3BE21 is a pluggable bushing current transformer from the SENTRON range, designed as an accessory for 3NJ6 in-line switch disconnectors. It converts a primary current of up to 150 A into a standard 5 A secondary signal for measuring instruments, with Class 1 accuracy and a 1.5 VA rated burden. The 21 mm cable opening accepts typical low-voltage feeder conductors, and the compact 44×65×30 mm body fits directly onto the switch disconnector frame without bolts or brackets.

Key Specifications

• 150/5 A ratio with FS 5 overcurrent limiting factor – the core saturates at 5× rated primary current, protecting downstream meters from short-circuit damage.
• Class 1 accuracy (IEC 61869‑2) with 1.5 VA burden – sufficient for panel ammeters and simple energy monitoring.
• 50/60 Hz operation, 0.72 kV rated operational voltage, 3 kV insulation.
• Weighs only 185 g, mounts directly on the 3NJ6 switch disconnector without additional hardware.