Electrical Installation; Electrical Installation Requirements - Mitsubishi MELSEC-WS0-CPU0 User Manual

Chapter 7
7

Electrical installation

Note
ATTENTION
Note
73
Electrical installation
7.1

Electrical installation requirements

This chapter deals with the electrical installation of the MELSEC-WS safety
controller in the control cabinet. You will find additional information on the electrical
connection of other devices to the MELSEC-WS safety controller in the section on
the respective device in Chapter 4.
Switch off the entire machine/system!
The system could start up unexpectedly while you are connecting the devices.
Observe the relevant safety standards!
All safety related parts of the installation (cabling, connected sensors and actuators,
configuration settings, EDM) must be according to the relevant safety standards (e.g.
IEC 62061 or ISO/EN 13849-1). This may mean that safety related signals need to
be redundant or that single channel signals need protected wiring or short circuit
detection by using test outputs and/or periodical function tests.
 Take into account that short circuits between test outputs and the corresponding
input cannot be detected.
 Consider if protected or separate cabling is required for these signals.
 The MELSEC-WS safety controller fulfills the EMC requirements in accordance
with the basic specification IEC 61000-6-2 for industrial use.
 Mitsubishi industrial safety devices are designed for local DC supply applications
only. If the device is used in power supply networks, e.g. according to IEC 61326-
3-1, additional protective measures have to be taken.
 Machines where safety devices are used must be installed and designed
according to the Lightning Protection Zone (LPZ) according to IEC 62305-1.
Required immunity levels can be achieved through the use of external protective
devices. The installed surge protective devices (SPD) should meet the
requirements according to IEC 61643-11.
 The installation must prevent common mode disturbances according to IEC
61000-4-16 in the frequency range from 0 Hz to 150 kHz.
 To ensure full electromagnetic compatibility (EMC), the mounting rail has to be
connected to functional earth (FE).
 The MELSEC-WS safety controller must be mounted in a control cabinet with at
least IP 54 enclosure rating.
 Electrical installation in accordance with IEC 60204-1
 The voltage supply of the devices must be capable of buffering brief mains
voltage failures of 20 ms as specified in IEC 60204-1.
 The voltage supply as well as all signals connected have to fulfill the regulations
for extra-low voltages with safe separation (SELV, PELV) in accordance with IEC
60664 and EN 50178 (equipment of electrical power installation with electronic
devices).
 You must connect all modules of the MELSEC-WS safety controller, the
connected protective devices (e.g. the EFI devices) as well as the voltage
supply/ies with the same 0 V DC (GND). The GND of the RS-232 interface is
connected internally to the GND of the supply of the CPU module (A2).
 If the RS-232 interface at the CPU module is used as an alternative to a network
module, the maximum permissible cable length is 3 m.