Hitachi HSC-2100 Hardware Manual page 12

(chapter 3, page 3-2)
In installation locations where there is a possibility of water leak, be sure to house
the programmable controller in a water-proof enclosure. Disregarding this rule
may result in hardware damage.
(chapter 3, page 3-3)
It may happen that the input voltage of the power supply module is within the
above specifications but it is close to the upper or lower limit. In these cases,
the user is advised to consider the input voltage as being abnormal and ask a
power supply management specialist for inspection of the module.
(chapter 3, page 3-6)
Construct an emergency stop circuit and an interlock circuit outside this
product. Unless they are so constructed, failure of this product may result in
machine breakdown or accident.
Keep the input and output currents of any I/O module within the maximum
permitted current values. If an overcurrent is allowed to flow in the I/O
module, the component part(s) involved may be damaged, resulting an
accident, fire, or product failure.
(chapter 3, page 3-6)
Do not use a transceiver, cellular phone, or the like near any I/O module. Such
communication equipment generates noise, which may result in malfunction or
system failure.
NOTICE
NOTICE
NOTICE
NOTICE
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