Fluence
New Member
Meh... when i powered up my LED panel that has 1491 LED, i've connected the multimeter to measure the Amps, and for my surprise the LED panel was consuming 9.32A, instead of 4.2A.
The configuration of my panel is like this:
125 strings of 7 Red LED - 2.2v 20mA each LED - Each string connected with one 470Ohm 1/2W resistor (yeah i could do it better but when i was about to finish the soldering on the panel i've remembered that Red LED are powered with 2.2v and not 3.3v...)
and
88 strings of 7 Green LED - 3.2v 20mA each LED - Each string connected with one 82Ohm 1/4W resistor
2500mA + 1760mA = 4260mA
I've bought a laptop Power Supply, with 24Vdc 5A 120W to power the panel.
The panel works great and all the lights are at full bright, (it flashes more than a flash grenade ;3), and the power supply doesn't get too hot, BUT, when i connect the multimeter it read 9.32A, i just don't understand... i mean, if it was really consuming 9.32A the power supply would get toasted, but it's all running smoothly and i don't understand why.
Another thing that's bothering me, it's the wires. I've connected the LED with UTP45 cable (the same we use to create networks) and it gets -very- hot near the entrance of the 24V, i'm thinking in separating the LED panel in about 10 parts and use 2 cooper wires with 2.5mm, but i wonder if that will be enough.
The configuration of my panel is like this:
125 strings of 7 Red LED - 2.2v 20mA each LED - Each string connected with one 470Ohm 1/2W resistor (yeah i could do it better but when i was about to finish the soldering on the panel i've remembered that Red LED are powered with 2.2v and not 3.3v...)
- Together, all resistors dissipate 23500 mW
- Together, the diodes dissipate 38500 mW
- Total power dissipated by the array is 62000 mW
- The array draws current of 2500 mA from the source.
and
88 strings of 7 Green LED - 3.2v 20mA each LED - Each string connected with one 82Ohm 1/4W resistor
- Together, all resistors dissipate 2886.4 mW
- Together, the diodes dissipate 39424 mW
- Total power dissipated by the array is 42310.4 mW
- The array draws current of 1760 mA from the source.
2500mA + 1760mA = 4260mA
I've bought a laptop Power Supply, with 24Vdc 5A 120W to power the panel.
The panel works great and all the lights are at full bright, (it flashes more than a flash grenade ;3), and the power supply doesn't get too hot, BUT, when i connect the multimeter it read 9.32A, i just don't understand... i mean, if it was really consuming 9.32A the power supply would get toasted, but it's all running smoothly and i don't understand why.
Another thing that's bothering me, it's the wires. I've connected the LED with UTP45 cable (the same we use to create networks) and it gets -very- hot near the entrance of the 24V, i'm thinking in separating the LED panel in about 10 parts and use 2 cooper wires with 2.5mm, but i wonder if that will be enough.