Hi @DigitalBob ! Thanks for your help. I'm waiting for the 470 Ohms resistor to arrive tomorrow. I tested with a 220 Ohms instead and this are the voltage value (see picture) but If the 470 resistor gives me the same results I will like to use that one to have less current as possible. Thanks
@DigitalBob said:
The 470 Ohm lowers the Led current, and slightly dimmer, but you can use 220 ohm
Great glad it worked out for you. You should read about 3 volts from ground to LED negative. I can't see what points your probes are on, maybe LED neg. and LED Pos. Anyway it works.
Campbell, CA. And you get free food for sure! Qiestion: how do I calculate how many Amperes I need on the 5v power supply? It has 1 BS2, 1 Xbee and 13 LED switches.
@DigitalBob said:
I don't know where your theater is, but if I ever visit I'll hit you up for discount popcorn
Alright bring on the Nachos. So 13 Led's lets go with 20 Ma ea. X 13, 260 = milliamp. The Bs2 uses about 3-4 Ma. plus pin load. Now the Xbee Wifi can draw up to 300 Ma. in transmit mode. Just to be on the safe side I'd go with 2-3 amp power supply.
The XBee will be the worst of it. An XBee Pro uses about 135mA when transmitting. To be safe, budget for 150mA.
Your LEDs in the buttons will take about 7mA when operating.
There's no spec on the BS2, so budget 100mA.
All added you get 150 + (13 * 7) + 100 = 341mA. Now double that (for safety) to 682mA and get the next larger standard supply. A 1A power supply should fit the bill nicely. Since this is a one-off build (i.e., you're not building 1000s and looking to save fractions of a penny) there is no need to skimp on the power supply, especially if you have long wires.
If you don't have it, get an app called ElectroDoc. There's a free version and a really inexpensive paid version (about $5). It's a great reference for everything electrical. If you have to run your 5v power a long distance then you want to make sure to size that wire enough to prevent excessive voltage drop.
You can get 40-70 amp power supplies on Amazon for about $25. So you can use several smaller ones for all of your rows or one larger master supply for the whole project. Just have a fuse for each row if your going to use one supply.
Comments
I would run with it. Simple, no extra wires
The 470 Ohm lowers the Led current, and slightly dimmer, but you can use 220 ohm
Hi @DigitalBob ! Thanks for your help. I'm waiting for the 470 Ohms resistor to arrive tomorrow. I tested with a 220 Ohms instead and this are the voltage value (see picture) but If the 470 resistor gives me the same results I will like to use that one to have less current as possible. Thanks
Great glad it worked out for you. You should read about 3 volts from ground to LED negative. I can't see what points your probes are on, maybe LED neg. and LED Pos. Anyway it works.
That's with a 5 volt power supply
Yes with 5V. I was testing the + and - of the switch.
All seems to be working with a 470 Ohm resistor! Voltage on the picture attached.
Thank you very much!
I don't know where your theater is, but if I ever visit I'll hit you up for discount popcorn
Campbell, CA. And you get free food for sure! Qiestion: how do I calculate how many Amperes I need on the 5v power supply? It has 1 BS2, 1 Xbee and 13 LED switches.
Alright bring on the Nachos. So 13 Led's lets go with 20 Ma ea. X 13, 260 = milliamp. The Bs2 uses about 3-4 Ma. plus pin load. Now the Xbee Wifi can draw up to 300 Ma. in transmit mode. Just to be on the safe side I'd go with 2-3 amp power supply.
The XBee will be the worst of it. An XBee Pro uses about 135mA when transmitting. To be safe, budget for 150mA.
Your LEDs in the buttons will take about 7mA when operating.
There's no spec on the BS2, so budget 100mA.
All added you get 150 + (13 * 7) + 100 = 341mA. Now double that (for safety) to 682mA and get the next larger standard supply. A 1A power supply should fit the bill nicely. Since this is a one-off build (i.e., you're not building 1000s and looking to save fractions of a penny) there is no need to skimp on the power supply, especially if you have long wires.
If you don't have it, get an app called ElectroDoc. There's a free version and a really inexpensive paid version (about $5). It's a great reference for everything electrical. If you have to run your 5v power a long distance then you want to make sure to size that wire enough to prevent excessive voltage drop.
You can get 40-70 amp power supplies on Amazon for about $25. So you can use several smaller ones for all of your rows or one larger master supply for the whole project. Just have a fuse for each row if your going to use one supply.