I've been asked to help program something for my schools Christmas parade float and I was wondering if Arduino would be better than what were trying to use currently.
Basically we're supposed to have some lights flash our schools name. Right now we're trying to figure out how to program a PLC to do it but it's taking a long time to figure out how it works... Would it be easier to use an Arduino to do it? We need each letter to flash on and then have the whole thing flash a few times.
can you give some more intel on the current PLC and your experience aswell as what setup the light needs to be (size, grid, leds or screen, more specs, etc..)?
The Arduino should be able to do that. You'll need some relays. Do you know how to wire-up a relay?
How many letters/channels do you need to control? The Arduino Uno has 14 I/O pins, so if you don't need any inputs you can easily-directly control 14 letters independently. The Arduino Mega has 54 I/O pins.
If you need more outputs/channels, and just need on/off control (no dimming), you can use shift registers to individually address as many channels as you wish. (I have some serially-controlled special-purpose LED-drivers that are basically shift registers controlling 48 LEDs from just 3 Arduino output pins.)
[u]Here[/u] is an example of a relay board with drivers so you can drive it from the 5V low-current Arduino outputs. (I haven't used this particular relay board, it's just an example I found.)
The PLC is an Allen-Bradley Micrologix 1000 and I have no experience with it.. as the for the lights I imagine it's going to be LED's and we only need to spell KTC. I don't know how to wire relays but this is for an electrical class so my instructor could probably help us. The lights will have to be reasonably large too since it's for a parade float.
Also, Would I be able to control it directly from my computer instead of using a battery pack or something?
you would have to go an determine how many LEDs you are going to use, in order to know how many i/o ports are at least required, and to determine what is the best approach for you.
The Arduino Uno has 14 I/O pins
Actually it has 20. 6 can be used for digital IO, or for analog input.
Sounds like you may want to get some LED strip lights and make large letters that way. Just need a 12V supply capable of enough current - about 20mA for every 3 LEDs in the strip.
On sale even:
http://www.dipmicro.com/store/index.php?page=2&act=viewCat&catId=511
Easy to have arduino control an relay to make them turn on/off - or 3 relays so you can cycle them at different times.
Arduino, 3 NPN transistors, 3 1N4001 diodes, 3 resistors, 3 relays.
Switching NPN Bipolar Transistor BC639 80V/1A - dipmicro electronics sink current thru relay coil
Standard Rectifier 50V/1A 1N4001 - dipmicro electronics dissipatee induced coil current
560 Ohm 1/4W Resistor ±1% 560R 561 - dipmicro electronics limit current from arduino pin into transistor base
Miniature SPDT Relay 12V - 10A@125VDC 833H-1C-C-12VDC - dipmicro electronics connect LED strip - to Gnd (12V -) when closed
Connect LED strip+ to battery+