EN Terminal Clamp AKL-8-W
RC-Junky English Conversion 4
The required value of the series resistor depends on 3 different factors:
• Level of the supply voltage (U
B
)
• Voltage of the LED (U
L
). Added together when connecting several LEDs in series
the individual stresses.
• Current of the LED (I)
The series resistance value (R) can be calculated using the following formula:
U
B
- U
L
R = ---------- U
L
= (U
L1
+ U
L2
+ U
L3
+ U
Ln
)
I
Example:
We have a supply voltage of 7.2 V and want a white LED with a supply voltage
3.4 V and 12 mA (= 0.012 A).
7.2 V - 3.4 V
R = ----------------- = 317 Ohms
0.012 A
However, since there is no resistance value of 317 Ohms available, we take the
closest available value of 330 Ohms.
Then the necessary power (P) of the resistor should also be checked:
P = (U
B
- U
L
) x I
P = (7.2 V - 3.4 V) x 0.012 A = 0.046 W
In this example, a standard resistor with a power of
0.250 W (1/4 W).
When connecting relays or other inductive loads (e.g. motors) free-wheeling diodes
(e.g. 1N4007) must be used.
The free-wheeling diodes must be connected in blocking direction parallel to the
consumer.
The enclosed 0 Ohm "resistors" can be used as a bridge if no in series resistor is
required at any output.