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EATON
www.eaton.com
Section 1: Introduction
Figure 1. Digitrip 1150 Trip Unit With Rating Plug and Frame
Module
This instruction book specifically covers the application of
Digitrip 1150 and 1150i trip units installed in the Series NRX-NF
frame or Series NRX-RF frame circuit breakers.
The styles of trip units consists of the Digitrip 1150 for
compliance with UL/ANSI standards and the 1150i for the IEC
standards applications.
The Digitrip 1150 and 1150i trip units may be applied on either
50 and 60 Hz systems.
The Digitrip 1150/1150i trip unit system consists of 3 parts, the
frame, the trip unit and the display. The frame module is fixed
to the circuit breaker. This module is matched to the frame
interruption rating and sensors of the circuit breaker and should
not be changed. The trip unit module contains the Digital
Signal Processor (DSP) that performs the measurements and
calculations for protection and metering. The display module
is the user interface and requires external control power to
operate.
The Digitrip 1150/1150i trip units work with either the current
sensors of the NF or RF frame Series NRX circuit breakers. The
appropriate rating plug must be matched to the frame and style
of circuit breaker that the trip unit is applied to.
Effective September 2013
Instructional Leaflet IL01301064E
Operating Manual for Series NRX
Digitrip Trip Units 1150 / 1150i
Figure 2. NRX NF Circuit Breaker with Digitrip 1150
