The Siemens 3NJ6920-3BD22 is a pluggable bushing current transformer designed as a direct-fit accessory for 3NJ6 in-line switch disconnectors with fuses. With Class 0.5 accuracy at 1.5 VA burden, it bridges the gap between basic Class 1 measurement and calibrated billing-grade metering.

Application

This 100/5 A current transformer is suited for low-voltage distribution applications requiring above-standard measurement accuracy — such as performance trending, energy audits, and power quality monitoring — without the cost of legal-for-trade calibration. The 5 A secondary output connects directly to standard panel meters, data loggers, and PLC analog inputs.

Installation

The pluggable design enables tool-free installation directly onto compatible 3NJ6 in-line switch disconnectors. The 21 mm bushing opening routes the primary conductor through the transformer core. The CT snaps into the dedicated accessory port — no additional wiring or mounting hardware is needed.

Decision Parameters