Dimmer for controlling the power consumption of a connectable load, in particular an LED light, having two parallel-connected, electrically isolated dimmer channels (K1, K2), namely a first dimmer channel and an adjacent second dimmer channel each with a channel control device (S1, S2), wherein each of the dimmer channels (K1, K2) is connected on the output side in parallel via respective terminals (A1, A2) to the load, each of the two dimmer channels (K1, K2) is configured as a measurement dimmer channel and in each case comprises a measurement device which is at least suitable for generating information about the behaviour of the electricity at a location in the respective dimmer channel (K1, K2), wherein the information contains an indication about the time of at least one zero crossing of an AC voltage in the respective dimmer channel (K1, K2), a main control device, which is at least suitable for generating control commands for the two parallel-connected, electrically isolated dimmer channels (K1, K2), and wherein each of the two dimmer channels is connected with a respective communication link to the main control device, which in each case is at least suitable for transmitting such control commands from the main control device to the respective channel control device of the measurement dimmer channel, wherein the main control device is set up to obtain the information via the communication links, wherein the main control device is set up to identify whether the respective times of the respective zero crossings of the sinusoidal AC voltage applied to the respective dimmer channel (K1, K2) are substantially synchronous, characterised in that the main control device is configured, by measuring a phase shift of the two AC voltages, to establish whether or not an appreciable phase shift is present, wherein an identified phase shift represents incorrect wiring. two parallel-connected, electrically isolated dimmer channels (K1, K2), namely a first dimmer channel and an adjacent second dimmer channel each with a channel control device (S1, S2), wherein each of the dimmer channels (K1, K2) is connected on the output side in parallel via respective terminals (A1, A2) to the load, each of the two dimmer channels (K1, K2) is configured as a measurement dimmer channel and in each case comprises a measurement device which is at least suitable for generating information about the behaviour of the electricity at a location in the respective dimmer channel (K1, K2), wherein the information contains an indication about the time of at least one zero crossing of an AC voltage in the respective dimmer channel (K1, K2), a main control device, which is at least suitable for generating control commands for the two parallel-connected, electrically isolated dimmer channels (K1, K2), and wherein each of the two dimmer channels is connected with a respective communication link to the main control device, which in each case is at least suitable for transmitting such control commands from the main control device to the respective channel control device of the measurement dimmer channel, wherein the main control device is set up to obtain the information via the communication links, wherein the main control device is set up to identify whether the respective times of the respective zero crossings of the sinusoidal AC voltage applied to the respective dimmer channel (K1, K2) are substantially synchronous, characterised in that the main control device is configured, by measuring a phase shift of the two AC voltages, to establish whether or not an appreciable phase shift is present, wherein an identified phase shift represents incorrect wiring.