IDEC Micro HG2G-5F Series, Instruction Sheet

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8.2 Grounding Cautions
If you decide to use a single power supply for the HG4G/3G, HG2G-5F with more than one
external device, take extra precautions. Some external devices may produce electrical
noise and short circuit the entire system setup, therefore, damaging the communication
circuit of the HG4G/3G, HG2G-5F and non-isolated Communication Device (i.e. PLC).
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 HG4G/3G, HG2G-5F and the
non-isolated communication device (i.e. PLC) to prevent damage.
8.3 Cautions for using the HG4G/3G, HG2G-5F connected to a personal computer
When connecting the HG4G/3G, HG2G-5F to a personal computer via the COM1/USB
interfaces, the HG4G/3G, HG2G-5F or the personal computer may break down depending
on the conditions of the personal computer. Make sure of the following cautions, in order to
prevent an accident.
・
If the personal 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 personal computer has a 2-pin power plug without ground lead, follow the procedure
below when connect the HG4G/3G, HG2G-5F to the personal computer.
(1) Pull out the power plug of the personal computer from the AC outlet.
(2) Connect the HG4G/3G, HG2G-5F to the personal computer.
(3) Insert the power plug of the personal computer into the AC outlet.