Sort of Means for Dealing with Input Analog Signals in PLC

Contraposing the problem that small-PLC or unitary PLC can't deal with input analog signals,the principle of double-tilted line ADC was brought forward,ADC is built with the familiar elements and the inner counter in PLC was applied.Thus the analog signals can be transformed into time signals,the PLC that can't deal with input analog signals formerly can achieve analog signals disposal only by few input spots.Capability price ratio was improved.The method has been used in the control system for electrode arc furnace.