7i96S PSU

Would there be anything wrong using a 24 to 5 vdc power buck to power a Mesa 7i96S card?

Or how about a cell phone charger?  Got plenty of those.

The 24v->5v buck converter I had gave me fits with intermitent low voltages that reset the 7i96S and caused what appears as network latency issues.

A 5v cell phone charger I hacked in there has been fine for a few months. I've got a Meanwell waiting for it to die, but haven't bothered to stick it in yet.

There have been a number of reports of people having problems with USB/phone chargers.
I would stick to a Meanwell MDR-10-5 (2 amp) or a bit higher... DIN rail mount or similar.

-older original Samsung chargers work perfectly
-avoid cheap china ones
-most buck converters work, but vary voltage with change in temperature, so i set them at 4.7-4.9V.
-never use buck/boost converters to power Mesa or relays.

rodw wrote:

There have been a number of reports of people having problems with USB/phone chargers.
I would stick to a Meanwell MDR-10-5 (2 amp) or a bit higher... DIN rail mount or similar.
 

Given that the 5v supply powers the logic section of the board I'd have to agree with rodw. It's the wrong part of the build to cut corners. The Meanwell power supplies are a safe bet and not too expensive.
 

Unlogic wrote:

rodw wrote:

There have been a number of reports of people having problems with USB/phone chargers.
I would stick to a Meanwell MDR-10-5 (2 amp) or a bit higher... DIN rail mount or similar.
 
Given that the 5v supply powers the logic section of the board I'd have to agree with rodw. It's the wrong part of the build to cut corners. The Meanwell power supplies are a safe bet and not too expensive.

 

You're both right, of course, about not cutting corners here; no argument from me on that one.

As long as the OP stays away from cheapo buck converters, that's the important part.

rodw post=300008 userid=20660There have been a number of reports of people having problems with USB/phone chargers.
I would stick to a Meanwell MDR-10-5 (2 amp) or a bit higher... DIN rail mount or similar.

I was hopping to get away with a single PSU for the system, control boards and step drivers.

So a RS style Meanwell would also work?

 

Yep.  If you want a multi-voltage PSU to keep it all in one package, the RS should be the ticket.

I've got one of their triples (5/12/24) running in a plasma.

You have to be careful here. I have a 12v/5v Meanwell power supply (in a frame) that is useless for this because the 5v side needs a load on it for the 12v side to work. The required load far exceeds the power draw of a Mesa card. It was suggested I add a ceramic resistor but the generated heat and power consumption made me scrap the idea. Seperate 24v and 5v DIN rail based power supplies are compact, less risky and much easier.

As fas as steppers are concerned, 48 volts is much better (if supported by your drivers) so you really end up needing 3 power supplies.
 

In case anyone needs 5 and 12V only, buy a PC power supply from Seasonic.
All new PC power supplies i have dismantled have a 12V rail only and the rest is done by dc-dc converters.
Word of warning though, they easily do 50 to 100A at 12V so shorts are very sparky!
They also have very good protections. In short, they are much higher quality than Meanwell, by far.