Wiring I/O Units
Section 3-5
3-5-1 Terminal Blocks
The terminal block of an I/O Unit can be removed by loosening the mounting
screws.
You do not have to remove the lead wires from the terminal block in or-
der to remove the block from an I/O Unit.
Terminal block mounting screws
Loosen the terminal block mounting screws to remove
the terminal block from the I/O Unit. Make sure the
mounting screws on the terminal block are tightened af
-
ter wiring is complete and the terminal block is re-
mounted to the I/O Unit.
3-5-2 Wiring Precautions
General
Electrical Noise
Take appropriate measures when any electrical device likely to produce noise is
connected to the PC as a load. Devices generating noise of more than 1,200 V
(such as electromagnetic relays and valves) require noise suppression. For
noise sources running on DC power, connect a diode in parallel with the coil of
each device.
When mounting a CPU Rack and an Expansion I/O Rack together on a mounting
plate, provide a ground to the mounting plate. The mounting plate must be plated
with a highly conductive surface in order to ensure noise immunity.
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