Mitsubishi 13J851, Руководство пользователя

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3.2.4 Control panel
PLCs are open-type devices (devices to be incorporated into other equipment) and
they have to be installed inside the control panel enclosure. *
*: Also, each network remote station needs to be installed inside the control panel.
However, the waterproof type remote station can be installed outside the control
panel.
(1) Electrical shock prevention
In order to prevent persons who are not familiar with the electric facility
such as the operators from electric shocks, the control panel must have the
following functions:
(a) The control panel must be equipped with a lock so that only the
personnel who has studied about the electric facility and have enough
knowledge can open it.
(b) The control panel must have a structure which automatically stops the
power supply when the panel is opened.
(c) For electric shock protection, use IP20 or greater control panel.
(2) Dustproof and waterproof features
The control panel also has the dustproof and waterproof functions.
Insufficient dustproof and waterproof features lower the insulation
withstand voltage, resulting in insulation destruction. The insulation in our
PC is designed to cope with the pollution level 2, so use in an environment
with pollution level 2 or below.
Pollution level 1: An environment where the air is dry and conductive dust
does not exist.
Pollution level 2: An environment where conductive dust does not usually
exist, but occasional temporary conductivity occurs due
to the accumulated dust.
Generally, this is the level for inside the control panel
equivalent to IP54 in a control room or on the floor of a
typical factory.
Pollution level 3: An environment where conductive dust exits and
conductivity may be generated due to the accumulated
dust.
An environment for a typical factory floor.
Pollution level 4: Continuous conductivity may occur due to rain, snow, etc.
An outdoor environment.
As shown above, the PLC can realize the pollution level 2 when stored in a control
panel equivalent to IP54.