MR16 on 24V loads?

[cmorda]

There has been some discussion about the MR16 and 24 volt loads. I was thinking about this solution. What do you think?

You could control both 12v and 24v loads (like the RGB floods)

Chris

[RJ]

There is a post where one of the users I kept telling to try it on 24v. They did and it ork perfect. No need to worry about it. Althought your layout does allow for both so thats on its own is cool.

RJ

[austindave]

Whether this can be done *could* depend on the power supplies. While it will work fine with batteries (since there's no ground "reference"), I've seen cases where power supplies can't be "stacked", since the negative output is connected to earth ground. If this is the case, connecting them in this way will short-out the first supply. Likewise, if the negative terminal is connected to the PS case, another set of problems & safety issues would be presented when stacking the PS's.

So, before connecting this way, I'd suggest verifying that the negative terminals are isolated from the PS cases and, separately, earth ground.

--Dave

[cmorda]

Thanks for your ideas. I didn't think about the bonded negative. I seem to recall AussiePhil getting zapped by the PS chassis when he was trying to generate 96 volts with computer power supplies.

I'll have to see what it would take to isolate the power supply pcb from the case. It might not be worth the trouble or be possible to do safely. And of course every one will probably be different. 

Chris

[blickensderfer]

Chris,

Take a look on ebay for 24v power supplies.  You are not allowed to view links. Register or Login

You can get one pretty cheap.

Dan

[mschell]

Here's the 24V power supply that I used with the MR16 and some LED floods that I built (Frank's Mighty Mini on DIYC).

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It's a 150W 24V supply.

I did have to put a heat sink on the 5V regulator on the MR16, but just got a TO-20 (or whatever the correct number is) HS from Radio Shack and bolted it on the regulator.

I didn't use this extensively this year, since it was late in the season, but did leave the unit turned on for several days in the garage.