BECKHOFF EP-xxxx-xxxx - Manual (Page 17)

Basic principles of explosion protection
EtherCAT Box Modules in potentially explosive areas 13
4.6 Usability of electrical equipment
4.6.1 Equipment category
The use of electrical equipment depends on the protection group and the surrounding atmosphere in which the
equipment is used. The corresponding equipment categories are listed in the table below.
4.6.2 Types of protection for electrical equipment
Types of protection are equipment measures that fall under the category of secondary explosion protection,
since they are intended to prevent the ignition of the explosive atmosphere. Apart from the equipment category,
the type of protection is also relevant for the determination of the usability.
There are various types of protection with different protection concepts. This document deals exclusively with
the type of protection “n” according to EN 60079-15. It defines the operation of electrical equipment in
potentially explosive atmospheres with the type of protection “n” as follows:
During normal operation and under defined abnormal conditions, electrical equipment with this type of
protection is not capable of igniting the surrounding explosive atmosphere.