User manual

tams elektronik
English LC modules
Examples for parallel connection of LEDs:
Power supply Series
resistors
Current per
LED
max. number
of LEDs
per output
transformer (~) | 12 V 1,5 kOhm 10 mA 10
transformer (~) | 12 V 820 Ohm 20 mA 5
transformer (~) | 15-16 V 2,2 kOhm 10 mA 10
transformer (~) | 15-16 V 1 kOhm 20 mA 5
transformer (~) | 18 V 2,7 kOhm 10 mA 10
transformer (~) | 18 V 1,2 kOhm 20 mA 5
The calculation of the series resistors is based on the following formula:
series resistor [kOhm] = power supply [V] / current [mA]
Note: The operating voltage with a.c. transformers is approx. 1,4 times the nominal voltage
given on the transformer. With d.c. power packs the operating voltage corresponds to the
given nominal voltage.
Serial connection of LEDs
With a serial connection all LEDs have to be connected (in series) via
one series resistor to the output. The current consumption of the LEDs
depends on the value of the series resistor. The higher the value, the
lower is the current. But, the LEDs are dimmer, the higher you choose
the series resistor´s value.
The number of LEDs you can connect in series depends on the transformer
´s nominal voltage and the colour of the LEDs. When connecting too many
LEDs, the voltage is not sufficient and the LEDs do not light.
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