The Siemens 3NJ6920-3BE23 is a pluggable bushing current transformer designed as a direct-fit accessory for 3NJ6 in-line switch disconnectors with fuses. It combines a 150/5 A ratio, Class 0.5 accuracy, and legal-for-trade calibration — providing a revenue-grade measurement solution with a standard 5 A meter interface.

Application

This calibrated CT supports billing-grade energy measurement on 150 A circuits in low-voltage distribution. The 5 A secondary output is the industry-standard interface for utility meters, sub-billing devices, and building energy management systems — ensuring straightforward integration without signal converters. The 14 mm bushing opening targets branch circuits with compact conductor cross-sections. Typical deployments include tenant submetering in multi-tenant commercial buildings, energy cost allocation in industrial facilities, and utility-grade measurement points.

Installation

The pluggable design enables tool-free installation directly onto compatible 3NJ6 in-line switch disconnectors. The 14 mm bushing opening routes the primary conductor through the transformer core. The CT snaps into the dedicated accessory port on the switch disconnector body — no additional wiring or mounting hardware is needed.

Decision Parameters