What this control unit does
The Schneider Electric ENW21415 is a Trip System 5.0A control unit for the EasyPact NW range of air circuit breakers. It provides LSI protection — long-time, short-time, and instantaneous — for standard industrial applications up to 690 V AC (IEC 60947-2). The microprocessor-based trip unit handles ratings from 800 to 4000 A, with a drawout mounting that lets you swap the control unit without pulling the breaker from the switchgear.
The trip unit rating of 800...4000 A covers the full EasyPack NW frame range — you set Ir (long-time pickup) from 0.4 to 1.0 x In across nine adjustable settings, so the same control unit can be dialed in for a 1000 A feeder or a 3200 A main. The LSI curve is fully programmable: long-time delay Tr from 0.5 to 24 s at 6 x Ir, short-time pickup Isd from 1.5 to 10 x Ir with delay Tsd from 100 to 400 ms, and instantaneous pickup Ii from 2 to 15 x In (or Off). That gives you selective coordination with downstream breakers without sacrificing arc-flash mitigation. The digital display shows instantaneous and maximum current per phase (I1, I2, I3, In) with ±1.5 % accuracy over a 0.2...1.2 In range. Fault indication covers earth fault, short-circuit, overload, and internal fault — no separate ground-fault relay needed for most installations. Zone selective interlocking (ZSI) is built in — when multiple EasyPact NW breakers are daisy-chained, the unit closest to the fault trips instantly while upstream units hold their delay, reducing arc energy. The control unit accepts 50/60 Hz networks and is rated for 3P, 4P configurations with neutral protection settings for 3D, 4D, or 3D + N/2.
Drawout mounting means the control unit slides into the breaker cradle without tools — the neutral connection is on the left side of the unit. Dimensions are 200 mm high, 55 mm wide, 75 mm deep, fitting standard EasyPact NW cubicle cutouts.