Patent ID: 7365547

Claim:
A circuit arrangement for a line test and for feeding a corrosion protection current into a two-wire line, comprising: a controllable ramp generator for producing a ramp voltage; at least one first test impedance to be connected between a first line of a two-wire line and a first voltage connection of said controllable ramp generator; at least one second test impedance to be connected between a second line of said two-wire line and a second voltage connection of said controllable ramp generator; at least one first and second controllable switch for connecting said ramp voltage to said first and second test impedances; and a programmable control device for controlling said ramp generator and said first and second controllable switches in such a way so that said ramp voltage is coupled to said two-wire line through said first and second test impedances in order to produce a corrosion protection current; said control device switching at least one of said first and second test impedances to the respective of said first and second lines for a line test.