Yes, seemed crazy, but much of the kit needed an inverter as well to get Mains from 12V car power. These are not very efficient.
The latest FireBrick (FB2900), available real soon now (literally waiting on safety test sign off now) will also have some DC power options. Yes, I may be crazy, but I decided "what the hell?", and these will be available at launch, along with rack mount kits.
The two options are (a) an automotive option aimed at cars and trucks and (maybe) boats allowing 12V and 24V supplies. Much more work than you expect as it needs all sorts of protection from voltage and current spikes you can get in such an environment. (b) The telco option for telecommunications racks with 48V DC.
The connector...
We decided on Anderson power-pole connectors, and will supply a plug and tail with the unit as well. They are excellent DC power connectors. The two variants are different colours and different keying too.
The application?
This is more tricky - who wants these? Well, telco racks with 48DC do exist, so that is one case. We do the FB6000 models with DC 48V supplies even (both DC+AC and DC+DC as dual power).
But will anyone really want in a car? Not sure.
Will anyone want in a boat? Maybe more likely... We have already had some enquiries, though I doubt we would meet the requirements to sell for boats (lots of salt water involved).
So what else?
Well, I want one myself? Why? Well I have a good 12V DC lead acid backup for the alarm/door system here. It lasts all day! They are common and simple. Alarms often need Internet access too. They are way better than a UPS for lasting all day if you have kit that can run on 12V DC.
The FireBrick FB2900 can provide the Internet access (e.g. a VDSL SFP) and connect to the alarm/door system anyway as well as some Ethernet connections for laptop in the event of main power failure. At around 5W for the FireBrick, and a max of 15W with USB and high power SFP, that is still a good lifespan from a 12V lead acid battery system.
The cost?
They cost a bit more than the AC version, but I can see there being all sorts of unexpected uses for this. We shall have to see how it goes - if you want DC powered serious network equipment, well, let us know. For now, with thousands of AC powered FB2900s on the shelf ready to ship, we have some DC models ready for evaluations in the next few days. Just talk to the team at A&A for more details.
I hope it was worth the investment in the DC options. It was my call to go for these options, DC and rack mount, to see how well they sell. If we only sell a few, we know for next time. Surprise me!
wISP type people may be grateful for it... Solar installs (DC) are not unheard of.
ReplyDeleteWhat kind of power draw does it take? Will a future variant be able to run off USB-C (or whatever we're using by then)
ReplyDeleteI said in the post, around 5W normally, 15W with USB and high power SFP fitted. Estimates.
DeleteHm, that's within the realms of USB-C with USB-PD.
DeleteI have a few RPi3s deployed on mobile units with Ravpower power banks as "UPS" devices, and those put out 5V 3A over USB-C.
Have you done EN60945 for EMC in marine applications?
ReplyDeleteWe're actually going through the stuff for the DC models now. I'll ask about boats :-)
DeleteWould I be right in assuming that many of the testing hoops you had to jump through no longer apply as soon as the device is DC powered? Or am I completely wrong?
ReplyDeleteThere are different requirements, yes. And a lot of the issues arounds mains power disappear. We're going through that now.
Delete@rtho782 - The safety requirements are usually gone (not because it's DC but because it's very low voltage), the automotive surge standards can be (very) hard, and the marine conducted+radiated emissions standards are (quite) hard.
DeleteNeed more evaluation really. And they seem to have got more expensive. We'll see how it goes.
ReplyDeleteIf you only need 15W max, could you have an 802.11af or at powered version with no internal PSU? You're already doing a 48VDC version so this seems close...
ReplyDeleteCould have POE go into the power supply, then a short patch cable from the PSU into whatever ethernet port you wanted, which has had the POE stripped off. Could be done without modifying the main PCB :)
DeleteAssuming the FB2900 is going to be core equipment then what problem does that solve?
DeletePoE is for distributing power out from a core location to other places, without needing two wires, surely?
You said "cars and boats". Just as likely to be caravans and motorhomes!
ReplyDeleteYachts in the Med and Touring Charter Coaches is more likely.
ReplyDeleteActually looking into a router+3G modem setup for my families sailboat.
ReplyDelete