Have you taken grounding into consideration?
The chassis is not connected to ground, tbh. Not really.
I built a 10 inch mini rack from aluminium extrusions
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Re: I built a 10 inch mini rack from aluminium extrusions
#42Earlier quoted context omitted.
Meanwell is the standard answer for this sort of thing; something in the SD-500 family or sized/optioned as you need. You'll have to do the connectors yourself; you may be able to find junction-post-to-barrel-plug leads of the right size and length off the shelf, but I'd be surprised, and soldering them would take less time than shopping for them.
The HP's power-supply is 19.5V: https://www.ebay.com/itm/235241551377 The SD-500 is available in 12V, 24V, and 48V, none of which adjust to that range: https://www.meanwell.com/Upload/PDF/SD-500/SD-500-SPEC.PDF Also, not sure why you're suggesting a DC-DC supply here? His input is AC.
Probably the idea is to have one big AC-DC PSU and then separate DC-DC regulators for each box from that rail.
Re: I built a 10 inch mini rack from aluminium extrusions
#43Nice writeup! Always thought extrusions were expensive. At least had found a company custom cutting them but the price was something like 20x what you got.
They are usually ludicrously expensive. But since Chinese manufacturers started using them for various small machine (3d printer, engraver...) frames, there's a now finally a cheaper supply.
Re: I built a 10 inch mini rack from aluminium extrusions
#44That’s a good looking build.
I considered going the 10 inch route too but ultimately decided on a small 19 mainly because I also wanted to fit a ATX build in there and most gear is 19 standardised
Re: I built a 10 inch mini rack from aluminium extrusions
#45These aluminum extrusions are called T-Slot, or as McMaster-Carr calls it, "T-Slotted Framing". Very common in industry; we have it everywhere on the Boeing factory floors. Not cheap, but very durable and reusable. Highly recommended. Check it out starting on page 2240 of your McMaster-Carr 132 catalog. They have all kinds of things you can mount up like monitor arms. It's an erector set toy for engineers. ;)
Do we have something similar to McMaster-Carr in Europe. I am looking at maybe Germany, Denmark, Sweden , North Europe and Scandinavia?
Similar - no (I'd be glad to be proven wrong), but you can find some small suppliers focused on specific niche like https://www.motedis.com if you need the profiles.
Re: I built a 10 inch mini rack from aluminium extrusions
#46Why use the original power bricks, with the space claim and awful routing, instead of just going to a single dc/dc... either directly if no individual power control is needed, or to a relay block or switch block if automated / manual individual control is needed?
One option is to stick a mini-UPS in-between the wall the devices. Such a thing is internally a handful of lithium cells and some DC outputs.
For powering a handful of things that consume less than 100W they are quite useful because they typically provide 2 or 3 DC outputs, and replace between 2 and 4 power bricks.
They also provide an hour or two of backup, quite useful in my country where the power sometimes goes out for a bit.
The downside is that I cant find decent ones in my country, and so I end up replacing mine every 2-3 years.
Re: I built a 10 inch mini rack from aluminium extrusions
#47It would be cool to design custom aluminum brackets for the fans. However I found that although ordering 3D prints is very cheap, using (for example) PCBWay for CNCing something out of aluminum is very expensive.
Try to avoid milling unless you absolutely need it. Better to go 2D with some tolerance and print small adapters, or use standard T-slot hardware, to connect it. It's often educational to browser McMaster just to get a feel for what standard parts even exist. For a bracket I would look at a laser or waterjet service. Sendcutsend is one of the more well known web shops and the pricing is OK for the convenience. Also l…
Thanks for the tips!
Re: I built a 10 inch mini rack from aluminium extrusions
#48I didn't originate this idea, but if you're curious about other options... I found success using an IKEA Helmer for my home lab. https://www.ikea.com/us/en/p/helmer-drawer-unit-on-casters-b...
First time I saw that was a dude who made 6x core2quad q6600 render farm
Re: I built a 10 inch mini rack from aluminium extrusions
#49Why use the original power bricks, with the space claim and awful routing, instead of just going to a single dc/dc... either directly if no individual power control is needed, or to a relay block or switch block if automated / manual individual control is needed?
I bought an 800w GaN USB-C charger from AliExpress (https://www.aliexpress.com/item/1005009093660588.html) and a handful of USB-C to barrel jack adapters. They're powering 2 EliteDesk G2s (35W) and 2 EliteDesk G3s (65W); not had any trouble so far though the GaN charger does run a bit hot (which I resolved by putting a fan under the charger).
Admittedly I can't be sure of the long-term reliability of the GaN charger, but its been running problem-free for over a year now.