Digital I/O Expansion And I/O Channel Numbering; Digital I/O Expansion And I/O Numbering - FATEK M Series User Manual

2-2 Digital I/O Expansion and I/O Numbering

Digital I/O means I/O with the discrete type status, including digital input (with initial X in DI
numbering) and digital output (with initial with Y in DO numbering). The DI and DO of M Series PLC can
both be expanded up to 1024 points (numbered as X0~X1023 and Y0~Y1023, each with 1024 points).
The status of input contacts (X0~X1023) of PLC come from the input signal connected to the digital
input terminal block on CPU Module or expansion module; while the status appears at digital output
terminal block of CPU Module and expansion module reflects the digital output relay (Y0~Y1023) status
inside PLC.
On M Series CPU Module, at the position right of the external terminal connector, there have labels
indicate the corresponding signal name. They label each terminal with numbers representing the
corresponding digital input contact Xn and digital output relay Yn. In the example of the CPU module in
ME3C6-1616T, The labels of the digital input contacts on the left side of the external terminal connector
are X0~15, S/S and the labels of the digital input contacts on the right side of the external terminal
connector are Y0~Y15, COM. Users only need to locate the printed label for each terminal to find out its
I/O number. The LED status display region also indicates the ON/OFF status for all DI(X0~X15) and
DO(Y0~Y15) on the main unit. Users can easily find each terminal with its I/O number and LED status
indication.
CPU Module Digital I/O Number
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M-Series PLC Expansion Module User Manual
Chapter 2 Expansion of M-Series PLC