Instruction Manual

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8.2 Cautions when connecting external devices
The Touch power supply is non-isolating. Interference or external noise from external
devices due to wiring may cause adverse effects on the internal circuits of the Touch or
external devices.
To prevent such damage, choose a proper solution depending on your system setup.
• Use a separate earth ground from the external noise source device.
• The wire for grounding should be thick and short in order to direct the noise from the
noise source device to the earth ground.
• Use a separate power supply from the external noise source device.
• Insert an isolator on the communication line of the Touch and the non-isolated
communication device (i.e. PLC) to prevent damage.
8.3 Cautions for using the Touch connected to a personal computer
When connecting the Touch to a computer via the Serial Interface (Port) or USB Interface,
the Touch or the computer may break down depending on the conditions of the computer.
Make sure of the following cautions, in order to prevent an accident.
• If the computer has a 3-pin power plug or power plug with a ground lead type.
Make sure to use a plug socket including a ground input electrode or ground the earth
lead, respectively.
• If the computer has a 2-pin power plug without ground lead, follow the procedure below
when connect the Touch to the computer.
(1) Pull out the power plug of the computer from the AC outlet.
(2) Connect the Touch to the computer.
(3) Insert the power plug of the computer into the AC outlet.