The C-DM-0006M-ULED module is designed for a DIN rail mounting. Likewise, the power supply for the LEDs (e.g. DR-60-12) is designed to be installed in the distribution cabinet, which means that in most cases the controlled voltage must be lead from the dimmer outlets over a longer distance.
If the voltage is 12 V, the losses in the cables are much higher and they should be taken into account. If the power supply allows fine tuning of the output voltage, the voltage of the source can be increased, which at least partially eliminates the losses in the cables. However, care must be taken not to overload some LED strips by increased voltage, if LED strips with different output or length of cables are supplied simultaneously.
The following diagram shows the results of a specific measurement of LED strip connection to the LED1 channel of the C-DM-0006M-ULED module, which is supplied by the DR-60-12 source. The strip is connected by a 30 m cable.
The LED strip used: 1 m of 60/NW 2200 CREE strip, parameters: 12 V, 36 W/m, 2200 lm/m
The source used:DR-60-12, the output of the source is set at 13.42 V
Cable: 2x1.5 CYKY, 30 m length
The dimming module: C-DM-0006M-ULED
Fig. 1. Measured voltage curve in a LED strip
The resistance of standard CYKY cables:
CYKY 1.5 resistance 12.5 Ω/km (info: PRAKAB)
CYKY 2.5 resistance 7.5 Ω/km
CYKY 4 resistance 4.7 Ω/km
Total resistance of the CYKY 1.5 cable for 30 meters: 0.75Ω ( 0.0125Ω/m x 30 x 2)
The voltage on the source output 13.42 V (it roughly corresponds to the voltage on the LED1 output).
The the LED strip voltage (maximum) 11.5 V
13.4 V – 11.5 V = 1.92 V, from which follows the current of 2.56 A and the power consumption of the LED strip is 295 W.
The measured values prove that even the power LED strip can be powered and dimmed over a longer distance without any problems. In order to reach the voltage of 12 V in the LED strip, you could use a source with an option of setting even higher voltage, or use a cable with a larger diameter (e.g. CYKY 2.5), but due to the fact that the closer the voltage in the LED is to the maximum, the more the efficiency decreases, and as the difference is relatively small, the specified example is applicable without any problems.
The diagram also illustrates the so-called "logarithmic characteristics" of the dimmer, which is normally implemented in the C-DM-0006M-ULED module.