What is a PLC Rack or PLC Chassis?

What is a PLC Rack or PLC Chassis? plc rack and slot 6ES7401-2TA00-0AA0 € Siemens Simatic S7-400 6ES7401-2TA00-0AA0 CR2 RACK, CENTRALIZED,18 SLOTS,2 SEGMENTS rack, plc rack, rack, s7-400, simatic, situs slot 123 View Rack and Slot from CS MISC at Quaid-e-Azam Degree College, Peshawar When using a modular PLC

situs slot 123 import snap7 IP = ' ' RACK = 0 SLOT = 1 plc = Client() print(_cpu_state()) I

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