Can LEDwiz handle AC power?

[supafraud]

Hello, does anyone know if LEDwiz can handle the AC juice (6 volts) coming from my ol EM pinball machine power supply? I'd like to use it to drive the lamps. Anyone know if that's a bad idea?

[WindDrake]

Don't feed the LEDWiz AC. DC only.

[drventure]

+1

If you need to control AC, use the LEDWiz to drive a reed relay or opto isolator circuit. And even then, I'd keep it to low voltage AC unless you know what you're doing.

That said, i've used an LEDWiz to control ELWire and that stuff uses ~70v ac (but low current).

But that was using optoisolators to control the AC, The LEDWiz never sees ac.

[supafraud]

Thanks for the info. I noticed that the pinball bulbs will still light up if I give them DC (I used on of the bulbs to test a pacdrive I'm also fiddling with) which I guess is no surprise because it's just electricity running through a filament. However I noticed with just the default 5(?) volts that comes out of the USB and who knows how many amps that they are pretty dim. If I get a power supply to feed them 6 volts DC running at 10 amps is that too much for it to handle?

[drventure]

Yeah, even if you push DC to the lamps, those are lamps, not IC's, so they're an inductive load, which the LEDWiz isn't really designed to handle.

[supafraud]

I see, is there a good tutorial on how to use the optoisolators in your setup? I'm pretty noobish when it comes to hardware but could probably pull it off if I saw it done.

[RandyT]

Yeah, even if you push DC to the lamps, those are lamps, not IC's, so they're an inductive load, which the LEDWiz isn't really designed to handle.

Actually, the LED-Wiz is designed to handle inductive loads.  However, when powering these, it is imperative that the +V of the load is also connected to the "Bank Voltage Select" terminal respective to the driver chip from which the load is being operated.

The main consideration is amperage draw, and yes, 10amps would be far too much for the LED-Wiz to drive directly.

RandyT

[supafraud]

OK, so it looks like 500ma is the max for ledwiz right? I said 10 amps because that's what the EM pinball transformer puts out for the lamps at 6v AC. Does anyone have any experience with powering these bulbs with DC and with lower amperage? I want to keep the fixtures that are already installed on the machine and to swap them over to LEDs runs about $1.20 per bulb which is a little pricey when you start counting on the bulbs on the playfield.

[drventure]

Hey Randy, thanks for clearing that up.

@supafraud
Definitely listen to RandyT's advice on LEDwiz topics!

I could swear I posted a circuit diagram of what I used in controlling ELWire via an ledwiz through opto isolators, but I can't seem to find the topic right now. I'll keep looking.

[supafraud]

Believe me, I am all ears! :-) OK, so here's a question that is related but I should maybe start a new thread. I Have a Sain Smart 8 SS Relay bank that is made for arduinos. From what I can tell (and again I'm a noob so maybe I'm wrong) I just feed it 5 volts and it will switch on higher voltage AC (like for a solenoid for example) shouldn't I be able to use this with ledwiz? I'm sending 5 volts to it from USB and the led lights don't come on. I'm not sure if that's because it wants AC hooked up to it, but from what I can tell it shouldn't matter. This is the page for it:

http://www.sainsmart.com/arduino-compatibles/module/relay/8-channel-5v-solid-state-relay-module-board-omron-ssr-4-pic-arm-avr-dsp-arduino.html

I would love if someone smarter than me could take a gander and let me know it this would work or if i'm taking crazy pills!

[MonMotha]

The LED-Wiz is a so-called "open collector" sink-only device.  Its outputs will never "supply voltage".  They essentially just turn on and off a path to ground.  This is why you can use it with various voltage supplies to fit your application requirements.

You can use this to drive an SSR or similar, but you need access to the "low side" of the current loop.  If I've found the board I think you've said you have, it requires a current SOURCE as it has it's own sink (an NPN transistor).  A bare SSR can be driven just like you would drive an LED (read the LED-Wiz docs - note that most SSRs have built in resistors), then the output side of the SSR can switch anything its rated for.  The LED-Wiz can also drive a mechanical relay, too.

You may be able to get by with using a "strong" pull-up resistor to provide the pilot to the NPN on your SSR board and letting the LED-Wiz "ground it out" to turn things off.  This would result in an inversion but may be usable.  It's not a simple no-passives direct connection, though.

In a nutshell, your Arduino SSR board has circuitry that is undesirable in this application.

[AHeaven]

Please note I read this while researching my newly ordered Sainsmart board and though it would not work with the ledwiz as stated, but it is not true.

Everything works great with the ledwiz ports connected to the input ports on the Sainsmart board and 5V power and ground.

[MTPPC]

Please note I read this while researching my newly ordered Sainsmart board and though it would not work with the ledwiz as stated, but it is not true.

Everything works great with the ledwiz ports connected to the input ports on the Sainsmart board and 5V power and ground.

You might want to do a little more research because some people are making certaion sainsmart boards work without the ledwiz.

http://vpuniverse.com/forums/topic/1069-i-created-a-sainsmart-cheap-relay-board-driver/

[AHeaven]

I know the USB Sainsmart boards can work with DOF or other solutions directly.

What I meant is a post above says the ledwiz cannot control the non-usb relay boards when in fact it does.

So the two options can work depending on your setup.