4 Electrical wiring and precautious SV600 Series User Manual
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Fig.4-10 Connection method of the digital output signals
Note: The default setting is 24V open-collector input and no need external 24V. HDI supports open-collector
signals which larger than 18V (default). For pulse signals need to larger than 9V input and the maximum
pulse that HDI can receive is 100KHz.
4.3 EMC
4.3.1 Definitions of related terms
EMC
：
EMC (Electromagnetic Compatibility) is the ability of electrical and electronic equipments to
work properly in an electromagnetic interference environment, also the ability not to release
electromagnetic interference to other devices or systems and make influence on the stabilize
working of other equipments.
Therefore, EMC includes two aspects:
Aspect 1: The electromagnetic interference caused by the device during normal operation
cannot exceed certain limits;
Aspect 2: The device must have sufficient immunity to the electromagnetic interference in the
environment, i.e. electromagnetic sensitivity.
First class environment:
The first environment includes civilian facilities. It also includes low-voltage power grids
facilities that are not directly connected through intermediate transformers and provide power to
civil buildings.
Second class environment:
The second environment includes all facilities other than those low-voltage supply networks
that directly connected to civil buildings.
C1 level Equipment:
The rated voltage of the electric drive system is less than 1000 V and used in the first
environment.
C2 level Equipment:
The rated voltage of the electric drive system is less than 1000 V and cannot be plug-in or
movable equipment. It can only be installed and commissioned by a professional when used in
the first environment.
C3 level Equipment: