So, recently I was looking around at Ubiquiti Networks. Are they really all that great? Well well, I was not short of impressed when I looked at their product offerings in greater detail. In addition to their excellent Wi-Fi access points and IP cameras, they also provide point-to-point visible light communications, switches, routers, and a UPS with only 24 V DC output. Their net gear runs U-boot and Linux, via the AirOS firmware image. So, it’s pretty much what I want, except that is proprietary software and proprietary drivers sprinkled in there.
Alas… there may be a caveat emptor in their UPS offerings. They may only provide battery discharge, not battery charge, and it is expected that chemistry-specific equipment (lead-acid polymer, etc.) be used for charging. Also, unlike the seasoned UPS vendors, this UPS does not appear to provide any surge protection at all, not even the equivalent of a PC “surge protector” power strip.
20191028/https://www.ui.com/
20191028/https://dl.ubnt.com/datasheets/edgemax/EdgeRouter_DS.pdf
20191028/https://dl.ubnt.com/ds/EdgePower
Unfortunately, Ubiquiti Networks started off with bad faith when it came to providing the corresponding source code to their software, and it took quite a bit of push before they finally provided it as they must per the GNU GPL license terms.
20191028/https://en.wikipedia.org/wiki/Ubiquiti_Networks
20191028/https://web.archive.org/web/20170430232455/http://libertybsd.net:80/ubiquiti/
20191028/https://web.archive.org/web/20170524235100/http://libertybsd.net/ubiquiti/
Alas, with that key information in mind, I had a better way to conduct my UPS search. Search for “DC UPS” and you’ll get much better results that are likewise geared up for network use, rather than generic appliance use that provides 120 VAC power output. The key here is that the DC voltage output will tend to be relatively high, and it is assumed that you will use DC-DC converters to get the lower voltages.
This particular one does run off of lead-acid batteries. It is not made obvious from the data sheet, but if you read in about the type of battery connectors used, binding-post connection, it’s pretty obvious it can’t be lithium-ion, by contrast.
20191028/DuckDuckGo ups dc output
20191028/https://www.seipower.com/24vdc/
20191028/https://www.seipower.com/wp-content/uploads/2018/08/2U24datasheet2.pdf
Now, I just ahd to check back at the NETGEAR site… as it turns out, NETGEAR still has strong business offerings, lest I worry that they became too consumer focused. No, Ubiquiti isn’t replacing them any time too soon. NETGEAR probably still does have better PoE switches, but if you also want a router function built-in, you may have to go with Ubiquiti. The NETGEAR flex PoE is really nice, though.
NETGEAR also has some recommendations for power redundancy too. They point to another manufacturer from their site. Please note: these are not UPS units! They just provide for redundant power sources.
20191028/DuckDuckGo netgear redundant power supply
20191028/https://www.netgear.com/business/products/switches/modules-accessories/rps5412.aspx#tab-resources
20191028/http://www.downloads.netgear.com/files/GDC/datasheet/en/RPS5412.pdf
20191028/http://www.optimal-power.com/
20191028/http://www.optimal-power.com/redundant.html