Patent ID: 6339805
Filing Date: 2002-01-15
Classification: G06F

Abstract:
A method for connecting an assembly of a programmable logic controller to a bus, the assembly being connectable to the bus via first and second supply lines and a signal line, the method comprising the steps of:controlling, with an evaluation circuit, a variable resistor to have a high resistance when the assembly is not connected to the bus, the variable resistor being arranged in at least one of the first and second supply lines; controlling, with the evaluation circuit, the variable resistor to have a low resistance when the assembly is connected to the bus only after a predetermined connection time has elapsed; and after the variable resistor has been controlled to have the low resistance, further controlling the variable resistor to have the high resistance, after a predetermined run-up time has elapsed, if a potential at a test input of the evaluation circuit is outside a predetermined value range.