The invention relates to LED lighting system comprising a power supply circuit and one or more LED modules. The power supply circuit is equipped with input terminals (K1, K2) for connection to a supply voltage source and first and second output terminals (K3, K4), and a driver circuit (I, II) coupled between the input terminals and the first and second output terminals for generating a LED current. The driver circuit (I, II) comprises a driver control circuit (II) equipped with an input terminal (K7) for increasing or decreasing the LED current in dependency of a signal present at the input terminal of the driver control circuit. The one or more LED modules comprise first and second input terminals (K5, K6) for connection to respectively the first and second output terminals of the power supply circuit, a series arrangement of a LED load (LS) and a current sensor (R1) coupled between the input terminals, a module control circuit for generating a current control signal at an output terminal of the module control circuit and coupled to the current sensor and to a reference signal generator (R3, R4, R5, Z1) for generating a reference signal representing a desired magnitude of the LED current, wherein the current control signal has a first value in case the desired value of the LED current is lower than the measured value of the LED current and a second value in case the desired value of the LED current is higher than the measured value of the LED current, and coupling circuitry (D1; Sg, DC, C1, C2) coupled during operation between the output terminal of the module control circuit and the input terminal of the driver control circuit, for communicating the first value of the current control signal to the input terminal of the driver control circuit and for blocking the second value, and wherein the signal at the input terminal of the driver control circuit has a default value when all the current control signals have their second value.