Date Code 20080918
Instruction Manual
SEL-749M Relay
Section 2
Installation
Instructi on Manual
Overview
The first steps in applying the SEL-749M Relay are installing and connecting
the relay. This section describes common installation features and
requirements.
To install and connect the relay safely and effectively, you must be familiar
with relay configuration features and options. You should carefully plan relay
placement, cable connections, and relay communication.
This section contains drawings of typical ac and dc connections to the
SEL-749M. Use these drawings as a starting point for planning your particular
relay application.
There are also instructions for using the versatile front-panel custom label
option. This allows you to use SEL
OGIC®
control equations and slide-in
configurable front-panel labels to change the function and identification of
target LEDs.
Relay Placement
Proper placement of the SEL-749M Relay helps make certain that you receive
years of trouble-free motor protection. Use the following guidelines for proper
physical installation of the SEL-749M.
Physical Location
You can mount the SEL-749M in a sheltered indoor environment (a building
or an enclosed cabinet) that does not exceed the temperature and humidity
ratings for the relay. The relay is IEC/EN 61010-1 rated at Installation/
Overvoltage Category II and Pollution Degree 2. This rating allows mounting
of the relay indoors or in an outdoor (extended) enclosure where the relay is
protected against exposure to direct sunlight, precipitation, and full wind
pressure, but neither temperature nor humidity are controlled.
You can place the relay in extreme temperature and humidity locations (see
). For EN 61010 certification, the SEL-749M
altitude rating is 2000 m (6560 feet) above mean sea level.
To comply with the requirements of the European ATEX standard for
hazardous locations, the SEL-749M must be installed in an enclosure that
meets the requirements of an Ex n enclosure rated IP54 or better. The
enclosure should be certified to these requirements or be tested for compliance
as part of the complete assembly. In North America, the relay is approved for
Class 1, Division 2, Groups A, B, C, D, and T4 hazardous locations.
Summary of Contents for SEL-749M
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