Discussion:
Make a high-speed router and also a 48-hour UPS battery supply
(too old to reply)
Thad Floryan
2014-03-15 06:56:33 UTC
Permalink
Raw Message
An email correspondent sent me the following 2 URLs earlier today and I
didn't have time to watch them until several hours ago due to runtimes.

What really surprised me was seeing ads/commercials embedded directly in
both these YouTube videos -- I hope this vile trend doesn't continue.

In any event --

Build a featureful router using an ITX motherboard, two NICs, and the
SmoothWall distro watching this mechanically-inept person doing it -- I'm
surprised he hasn't lost any fingers, hands, feet, or his life by now. :-)

Hak5: Building a high performance home router



runtime 48:20

48-hour backup battery supply for your el-cheapo UPS system whose battery
has bit the big one.

Build a 48 Hour Backup Computer Power Supply - SYSTM



runtime 24:36

Lots of caveats and liability disclaimers in the above video makes
one wonder whether it's even worth doing, but if you want to operate
through a 2-day power outage this is one solution.

And their safety tips should NOT be dismissed or ignored.

Thad
sms
2014-03-15 15:55:20 UTC
Permalink
Raw Message
On 3/14/2014 11:56 PM, Thad Floryan wrote:

I think I'd buy an Intel NUC that has a PCIe Mini slot (for a second
NIC) that runs off of 12V and use a 12V deep cycle car battery.

<http://techreport.com/news/25956/intel-bay-trail-nuc-is-available-online>

$145. Add a small SSD and some memory and you're done. It comes with the
PCIe slot occupies by a wireless card but you can change that.

I have an Atom version that I won at a conference. Pretty nice. No
expansion slot on the model I have. I use a USB Wireless thingee. I
installed Linux Mint but I think I'm going to use it for a PBX.
Thad Floryan
2014-03-15 19:08:19 UTC
Permalink
Raw Message
Post by sms
I think I'd buy an Intel NUC that has a PCIe Mini slot (for a second
NIC) that runs off of 12V and use a 12V deep cycle car battery.
<http://techreport.com/news/25956/intel-bay-trail-nuc-is-available-online>
[...]
Hi Steven,

First I've heard of the NUC; thanks for the URL!

FYI, there's no such thing as a 'deep cycle car battery' because the
requirements for starting a car differ dramatically from those for a
powered wheelchair or a trolling (fishing) motor or a golf cart.

A car battery is relatively light-weight because the lead plates are
thin. A true deep-cycle battery is heavy (starting at 50 pounds) due
to the extremely thick lead plates.

I have a bunch of marine deep-cycle batteries for use with telescopes
and unless I use a cart I have to carry two at a time, one hanging from
each arm, just to maintain my balance. You can see some of the battery
packs I use for my telescopes here -- I bought the marine deep-cycle
batteries at Costco and put them in Cabelas battery cases -- I have more
now than what's shown in this almost 10-year-old photo and I have better
maintainer/charger units for the marine deep-cycle batteries now than
what's seen atop the battery cases in this photo:

Loading Image... 59kB

Thad
sms
2014-03-15 20:30:48 UTC
Permalink
Raw Message
Post by Thad Floryan
Post by sms
I think I'd buy an Intel NUC that has a PCIe Mini slot (for a second
NIC) that runs off of 12V and use a 12V deep cycle car battery.
<http://techreport.com/news/25956/intel-bay-trail-nuc-is-available-online>
[...]
Hi Steven,
First I've heard of the NUC; thanks for the URL!
FYI, there's no such thing as a 'deep cycle car battery' because the
requirements for starting a car differ dramatically from those for a
powered wheelchair or a trolling (fishing) motor or a golf cart.
Right, except the starting batteries for the Prius and Camry hybrid
actually are deep cycle batteries.

<http://www.amazon.com/Optima-Batteries-8171-767-DS46B24R-YellowTop/dp/B006VFEJJQ>

<http://www.elearnaid.com/opd51yetopba.html>
Roy
2014-03-15 21:59:12 UTC
Permalink
Raw Message
Post by sms
Post by Thad Floryan
Post by sms
I think I'd buy an Intel NUC that has a PCIe Mini slot (for a second
NIC) that runs off of 12V and use a 12V deep cycle car battery.
<http://techreport.com/news/25956/intel-bay-trail-nuc-is-available-online>
[...]
Hi Steven,
First I've heard of the NUC; thanks for the URL!
FYI, there's no such thing as a 'deep cycle car battery' because the
requirements for starting a car differ dramatically from those for a
powered wheelchair or a trolling (fishing) motor or a golf cart.
Right, except the starting batteries for the Prius and Camry hybrid
actually are deep cycle batteries.
<http://www.amazon.com/Optima-Batteries-8171-767-DS46B24R-YellowTop/dp/B006VFEJJQ>
<http://www.elearnaid.com/opd51yetopba.html>
Maybe on some models of the Prius but my car used a Japanese motorcycle
battery. It finally died after 11 years :-)
Thad Floryan
2014-03-15 19:50:00 UTC
Permalink
Raw Message
Post by sms
I think I'd buy an Intel NUC that has a PCIe Mini slot (for a second
NIC) that runs off of 12V and use a 12V deep cycle car battery.
<http://techreport.com/news/25956/intel-bay-trail-nuc-is-available-online>
[...]
Hi Steven,

Hmmm, this comment there surprised me:

"At least the Celeron runs at 2.4GHz all the time."

which implies no CPU scaling so that means it's going to be consuming
full-power all the time. Per Intel's page, that's 12VDC, 36W.

The IR input and the other ports make a strong statement the NUC is
intended as the center of a home theater system as we also see on
that page per:

" ... will allow you to drive your home entertainment experience
" from the 4x4 form factor, so you can create a digital media
" center or personal cloud for your media files that fits in the
" palm of your hand.

Another "gotcha" is I cannot find any motherboard pictures or any
statement that, for example, a second NIC can be added which would
be necessary for use as a router though the Intel pages does state:

" Half-length PCIe* mini-card slot (used by pre-installed
" wireless card)

which implies one will need to unplug and toss that wireless card
assuming one can find a GiGE NIC that fits a PCIe mini-card slot

Also. the only hardware (besides the dual-core CPU itself) that's
specified is "Intel Wireless-N 7260BN" which means that whatever
OS is chosen for installation will need to support that and/or the
onboard NIC and/or a second GiGE NIC replacing the Intel wireless
depending how one intends to use the router.

If you pursue this with the NUC, please keep us informed.

Thad
sms
2014-03-15 21:28:10 UTC
Permalink
Raw Message
Post by Thad Floryan
Post by sms
I think I'd buy an Intel NUC that has a PCIe Mini slot (for a second
NIC) that runs off of 12V and use a 12V deep cycle car battery.
<http://techreport.com/news/25956/intel-bay-trail-nuc-is-available-online>
[...]
Hi Steven,
"At least the Celeron runs at 2.4GHz all the time."
which implies no CPU scaling so that means it's going to be consuming
full-power all the time. Per Intel's page, that's 12VDC, 36W.
The IR input and the other ports make a strong statement the NUC is
intended as the center of a home theater system as we also see on
" ... will allow you to drive your home entertainment experience
" from the 4x4 form factor, so you can create a digital media
" center or personal cloud for your media files that fits in the
" palm of your hand.
Another "gotcha" is I cannot find any motherboard pictures or any
statement that, for example, a second NIC can be added which would
" Half-length PCIe* mini-card slot (used by pre-installed
" wireless card)
Right, you'd remove that wireless card and stick in a PCIe Mini Card
NIC. You'd have to figure out how to get that extra RJ45 (or two)
jack(s) into the back.

<http://www.startech.com/Networking-IO/Adapter-Cards/Mini-PCI-Express-Gigabit-Ethernet-Network-Adapter-NIC-Card~ST1000SMPEX>

<http://www.bvm-store.com/ProductDetail.asp?fdProductId=548>

<http://www.bvm-store.com/ProductDetail.asp?fdProductId=547>

Those NUCs are a good deal since they come with the CPU. The power
supply is a pretty ginormous brick. The one that came with mine is this
one:
<http://www.sinpro.com.tw/products_detail_2.aspx?b_class=I.T.E.&name=SPU65&bc_sn=19&c_sn=50>,
the -105 model. I added a second 5.5/2.1 power plug to the cable and
also power a small 15" HDMI monitor. Some of the NUC models use a 19V
supply.
Roy
2014-03-15 19:34:01 UTC
Permalink
Raw Message
Post by Thad Floryan
An email correspondent sent me the following 2 URLs earlier today and I
didn't have time to watch them until several hours ago due to runtimes.
What really surprised me was seeing ads/commercials embedded directly in
both these YouTube videos -- I hope this vile trend doesn't continue.
In any event --
Build a featureful router using an ITX motherboard, two NICs, and the
SmoothWall distro watching this mechanically-inept person doing it -- I'm
surprised he hasn't lost any fingers, hands, feet, or his life by now. :-)
Hak5: Building a high performance home router
http://youtu.be/71S9fek0FKA
runtime 48:20
...
Seems to be lots of time and money spent instead of buying a real
router. The "production" version of Smoothwall was released in 2007
which is a bad sign.

My suggestion is Mikrotik. Here is a $70 one capable of 300 Mbps.

http://routerboard.com/RB951G-2HnD

If you need to go faster, Mikrotik has a complete line that all run the
same OS which is being updated and maintained. You can also buy their
RouterOS and install it on your own hardware
Thad Floryan
2014-03-15 20:16:49 UTC
Permalink
Raw Message
Post by Roy
Post by Thad Floryan
[...]
Build a featureful router using an ITX motherboard, two NICs, and the
SmoothWall distro watching this mechanically-inept person doing it -- I'm
surprised he hasn't lost any fingers, hands, feet, or his life by now. :-)
Hak5: Building a high performance home router
http://youtu.be/71S9fek0FKA
runtime 48:20
...
Seems to be lots of time and money spent instead of buying a real
router. The "production" version of Smoothwall was released in 2007
which is a bad sign.
Hi Roy,

Are we looking at the same thing? Here:

http://distrowatch.com/table.php?distribution=smoothwall

SmoothWall's most recent release (RC3) is 17-SEP-2013 and RC4
is 12-DEC-2013.

Frankly, any Linux OS running on a box with 2 (or more) NICs
could be configured as a router.
Post by Roy
My suggestion is Mikrotik. Here is a $70 one capable of 300 Mbps.
http://routerboard.com/RB951G-2HnD
If you need to go faster, Mikrotik has a complete line that all run the
same OS which is being updated and maintained. You can also buy their
RouterOS and install it on your own hardware
Interestng. I'm curious as to whose [presumed] managed GiGE 5-port module
is being used in their RB951G-2HnD; I couldn't find anything searching
that on their website, but Googling:

what managed switch is used in the Mikrotik RB951G-2HnD

did find this page which answers that question noting Mikrotik uses
at least 5 different modules with the Atheros8327 being used in the
RB951G-2HnD.

http://wiki.mikrotik.com/wiki/Manual:Switch_Chip_Features

Your comment about buying RouterOS and using it on one's own
hardware is puzzling: wouldn't the RouterOS only function with
the switch modules stated on the immediately above URL?

Thad
Thad Floryan
2014-03-15 20:37:34 UTC
Permalink
Raw Message
Post by Thad Floryan
[...]
Interestng. I'm curious as to whose [presumed] managed GiGE 5-port module
is being used in their RB951G-2HnD; I couldn't find anything searching
what managed switch is used in the Mikrotik RB951G-2HnD
did find this page which answers that question noting Mikrotik uses
at least 5 different modules with the Atheros8327 being used in the
RB951G-2HnD.
http://wiki.mikrotik.com/wiki/Manual:Switch_Chip_Features
[...]
Atheros 8327 data sheet here:

[PDF] AR8327 AR8327N - WikiDevi
https://wikidevi.com/files/Atheros/specsheets/AR8327_AR8327N.pdf

Qualcomm Atheros AR8327 and AR8327n | intelligraphics.com
http://intelligraphics.com/qualcomm-atheros-ar8327and-ar8327n/

PDF] AR8327/AR8327N Seven-port Gigabit Ethernet Switch - LaFi
https://lafibre.info/images/doc/201106_spec_AR8327.pdf

Thad
Roy
2014-03-15 21:57:51 UTC
Permalink
Raw Message
Post by Thad Floryan
Post by Roy
Post by Thad Floryan
[...]
Build a featureful router using an ITX motherboard, two NICs, and the
SmoothWall distro watching this mechanically-inept person doing it -- I'm
surprised he hasn't lost any fingers, hands, feet, or his life by now. :-)
Hak5: Building a high performance home router
http://youtu.be/71S9fek0FKA
runtime 48:20
...
Seems to be lots of time and money spent instead of buying a real
router. The "production" version of Smoothwall was released in 2007
which is a bad sign.
Hi Roy,
http://distrowatch.com/table.php?distribution=smoothwall
SmoothWall's most recent release (RC3) is 17-SEP-2013 and RC4
is 12-DEC-2013.
Yes, we are looking at the same thing. These are both RC versions. RC
equals release candidate. In other words, they are Beta versions. the
last released production version is 3.0 from 2007
Post by Thad Floryan
Frankly, any Linux OS running on a box with 2 (or more) NICs
could be configured as a router.
Post by Roy
...
Roy
2014-03-15 22:16:14 UTC
Permalink
Raw Message
Post by Thad Floryan
...
Post by Roy
If you need to go faster, Mikrotik has a complete line that all run the
same OS which is being updated and maintained. You can also buy their
RouterOS and install it on your own hardware
Interestng. I'm curious as to whose [presumed] managed GiGE 5-port module
is being used in their RB951G-2HnD; I couldn't find anything searching
what managed switch is used in the Mikrotik RB951G-2HnD
did find this page which answers that question noting Mikrotik uses
at least 5 different modules with the Atheros8327 being used in the
RB951G-2HnD.
http://wiki.mikrotik.com/wiki/Manual:Switch_Chip_Features
Your comment about buying RouterOS and using it on one's own
hardware is puzzling: wouldn't the RouterOS only function with
the switch modules stated on the immediately above URL?
Thad
Mikrotik has a bridge function which will handle unlike interfaces (eg
wifi and ethernet) and also will act as a software switch. The latter
case is when disparate or multiple chips are used (as in some models) or
in systems without any hardware switch chips.

So you could build a system with multiple ethernet interfaces and run
RouterOS on it just fine. I have run RouterOS in a virtual machine on
my laptop just to test configurations.

RouterOS comes in versions for different processor chips so if you are
going to try it on a PC, make sure you get the x86 one. I use the ISO
file and just boot it with my virtual machine
Marcus Allen
2014-03-16 04:49:34 UTC
Permalink
Raw Message
Post by Thad Floryan
Frankly, any Linux OS running on a box with 2 (or more) NICs
could be configured as a router.
A single NIC should work just as well, from a functional perspective. You
probably want two or more for the additional throughput capability or
perhaps for simple link redundancy, but for basic router functions, one is
all that's needed.
Thad Floryan
2014-03-16 05:56:13 UTC
Permalink
Raw Message
Post by Marcus Allen
Post by Thad Floryan
Frankly, any Linux OS running on a box with 2 (or more) NICs
could be configured as a router.
A single NIC should work just as well, from a functional perspective. You
probably want two or more for the additional throughput capability or
perhaps for simple link redundancy, but for basic router functions, one is
all that's needed.
Hi Marcus,

Scratchin' my head here, how could one have a functional router with
only one NIC?

Looking at this simply ('<===>' is Ethernet):

[ LAN ] <===> [ ROUTER ] <===> [ INTERNET via DSL, cable, etc ]

Thad
Roy
2014-03-16 06:11:15 UTC
Permalink
Raw Message
Post by Thad Floryan
Post by Marcus Allen
Post by Thad Floryan
Frankly, any Linux OS running on a box with 2 (or more) NICs
could be configured as a router.
A single NIC should work just as well, from a functional perspective. You
probably want two or more for the additional throughput capability or
perhaps for simple link redundancy, but for basic router functions, one is
all that's needed.
Hi Marcus,
Scratchin' my head here, how could one have a functional router with
only one NIC?
[ LAN ] <===> [ ROUTER ] <===> [ INTERNET via DSL, cable, etc ]
Thad
Off the top of my head:

1) Two subnets overlaid on the same ethernet. The router handles the
Inter-subnet traffic. Check out hairpin routing

2) The ethernet has VLANS and the router goes between the VLANs

3) VPN from router to some distant device.

4) IPV6 tunnel to a tunnel broker giving the ethernet IPV6 support.

5) Proxyarp support

6) Services the router supplies like DNS, VPN, NTP, DHCP

7) Web caching

Combinations of some or all of the previous ones makes it more
complicated.

You are right though, a one-armed router is not typical. I have one
router doing fuctions 1,2,3,4,6 although it does have 10 ethernet
interfaces.
sms
2014-03-16 16:24:34 UTC
Permalink
Raw Message
Post by Thad Floryan
Post by Marcus Allen
Post by Thad Floryan
Frankly, any Linux OS running on a box with 2 (or more) NICs
could be configured as a router.
A single NIC should work just as well, from a functional perspective. You
probably want two or more for the additional throughput capability or
perhaps for simple link redundancy, but for basic router functions, one is
all that's needed.
Hi Marcus,
Scratchin' my head here, how could one have a functional router with
only one NIC?
[ LAN ] <===> [ ROUTER ] <===> [ INTERNET via DSL, cable, etc ]
I suspect that he means a wireless router with a USB dongle for
wireless. You could also use USB to wired Ethernet. So technically you
don't need any NICs at all, except that a USB adapter is really a NIC.
Marcus Allen
2014-03-17 03:08:38 UTC
Permalink
Raw Message
Post by Thad Floryan
Post by Marcus Allen
Post by Thad Floryan
Frankly, any Linux OS running on a box with 2 (or more) NICs
could be configured as a router.
A single NIC should work just as well, from a functional perspective. You
probably want two or more for the additional throughput capability or
perhaps for simple link redundancy, but for basic router functions, one is
all that's needed.
Hi Marcus,
Scratchin' my head here, how could one have a functional router with
only one NIC?
[ LAN ] <===> [ ROUTER ] <===> [ INTERNET via DSL, cable, etc ]
Think "router on a stick" and tagged VLANs.

I install enterprise network gear for a living and about 70% of the time I'm
given a network design that incorporates a "single" interface. That
interface is typically built up from multiple copper Gig interfaces (or
10Gig or 40Gig fiber interfaces), but they're aggregated with 802.1q and
LACP so that they appear to be a single -fat- interface.

About 30% of the time I build to a network design that uses different
physical interfaces for 'external' versus 'internal' VLANs, but I always
point out to my customers that that's not required and is usually a less
efficient use of their resources.

Logically, it's helpful to think of a router as having two or more
interfaces, but physically, there only needs to be at least one.
Thad Floryan
2014-03-17 08:46:35 UTC
Permalink
Raw Message
Post by Thad Floryan
[...]
Scratchin' my head here, how could one have a functional router with
only one NIC?
[ LAN ] <===> [ ROUTER ] <===> [ INTERNET via DSL, cable, etc ]
[...]
[...]
1) Two subnets overlaid on the same ethernet. The router handles the
Inter-subnet traffic. Check out hairpin routing
2) The ethernet has VLANS and the router goes between the VLANs
3) VPN from router to some distant device.
4) IPV6 tunnel to a tunnel broker giving the ethernet IPV6 support.
5) Proxyarp support
6) Services the router supplies like DNS, VPN, NTP, DHCP
7) Web caching
Combinations of some or all of the previous ones makes it more complicated.
You are right though, a one-armed router is not typical. I have one
router doing fuctions 1,2,3,4,6 although it does have 10 ethernet
interfaces.
[...]
I suspect that he means a wireless router with a USB dongle for
wireless. You could also use USB to wired Ethernet. So technically you
don't need any NICs at all, except that a USB adapter is really a NIC.
and
Post by Thad Floryan
[...]
Think "router on a stick" and tagged VLANs.
I install enterprise network gear for a living and about 70% of the time I'm
given a network design that incorporates a "single" interface. That
interface is typically built up from multiple copper Gig interfaces (or
10Gig or 40Gig fiber interfaces), but they're aggregated with 802.1q and
LACP so that they appear to be a single -fat- interface.
About 30% of the time I build to a network design that uses different
physical interfaces for 'external' versus 'internal' VLANs, but I always
point out to my customers that that's not required and is usually a less
efficient use of their resources.
Logically, it's helpful to think of a router as having two or more
interfaces, but physically, there only needs to be at least one.
Thank you very much, gentlemen, for your replies!

I been retired since 2008 and haven't kept up and remained current with
networking technologies other than knowing "faster is better". :-)

Learn something new every day.

Thad
Kevin McMurtrie
2014-03-17 06:29:07 UTC
Permalink
Raw Message
Post by Thad Floryan
An email correspondent sent me the following 2 URLs earlier today and I
didn't have time to watch them until several hours ago due to runtimes.
What really surprised me was seeing ads/commercials embedded directly in
both these YouTube videos -- I hope this vile trend doesn't continue.
In any event --
Build a featureful router using an ITX motherboard, two NICs, and the
SmoothWall distro watching this mechanically-inept person doing it -- I'm
surprised he hasn't lost any fingers, hands, feet, or his life by now. :-)
Hak5: Building a high performance home router
http://youtu.be/71S9fek0FKA
runtime 48:20
48-hour backup battery supply for your el-cheapo UPS system whose battery
has bit the big one.
Build a 48 Hour Backup Computer Power Supply - SYSTM
http://youtu.be/jX1OQZ1B6m0
runtime 24:36
Lots of caveats and liability disclaimers in the above video makes
one wonder whether it's even worth doing, but if you want to operate
through a 2-day power outage this is one solution.
And their safety tips should NOT be dismissed or ignored.
Thad
May routers run off 9-16 VDC so it's trivial to put them on a battery.
LiFePO4 and lead acid are trivial to charge. LiPo can be float charged
as long as you chose a temperature-compensated voltage that will never
hit 100% charge. Meanwell makes 12VDC SMPS with adjustable output.
Thad Floryan
2014-03-17 08:33:20 UTC
Permalink
Raw Message
Post by Kevin McMurtrie
Post by Thad Floryan
[...]
Build a 48 Hour Backup Computer Power Supply - SYSTM
http://youtu.be/jX1OQZ1B6m0
runtime 24:36
Lots of caveats and liability disclaimers in the above video makes
one wonder whether it's even worth doing, but if you want to operate
through a 2-day power outage this is one solution.
And their safety tips should NOT be dismissed or ignored.
May routers run off 9-16 VDC so it's trivial to put them on a battery.
LiFePO4 and lead acid are trivial to charge. LiPo can be float charged
as long as you chose a temperature-compensated voltage that will never
hit 100% charge.
Hi Kevin,

"LiPo"? Lithium-Polonium? Polonium is highly radioactive:

http://en.wikipedia.org/wiki/Polonium

Does its heat boil water into steam turning a generator creating
AC which is then converted to DC in the battery package? :-)

I can handle radioactives safely, but, somehow, I don't think that's
what you meant, so I Googled "LiPo battery" and found this:

Lithium polymer battery - Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/Lithium_polymer_battery

which seems more suitable for consumers and home use. :-)

Battery types are frequently identified by their primary elements
e.g., NiCd (Nickel-Cadmium), NiMH (Nickel Metal Hydride), Pb (sealed
Lead battery), LiIon (Lithium Ion), AgZn (Silver-Zinc), ZnC/ZnCl2
(Zinc-Carbon/Zinc-Chloride), AgHg (Silver-Mercury button cells),
ZnBr2 (Zinc-Bromine), NaS (Sodium-Sulfur), NaNiCl2 (Sodium-Nickel-
Chloride), and more which is why "LiPo" threw me off. According to
the Wikipedia article, these are the common acronyms for the same
lithium polymer battery type:

Li-poly, Li-Pol, LiPo, LIP, PLI or LiP

Ugh. "LiP" would be Lithium Phosphorus -- sounds very wicked. :-)

and they're rechargeable and often used in cell phones. Hmmm, my
two current cellphones use Li-Ion batteries. The Wikipedia article
states this:

The advantages of Li-ion polymer over the lithium-ion design
include potentially lower cost of manufacture, adaptability to a
wide variety of packaging shapes, reliability, and ruggedness,
with the disadvantage of holding less charge. Lithium-ion
polymer batteries started appearing in consumer electronics
around 1995.

That "less charge" for LiPo bugs me and the reason is "lower cost"
which has a certain negative connotation.
Post by Kevin McMurtrie
... LiPo can be float charged
as long as you chose a temperature-compensated voltage that will never
hit 100% charge. Meanwell makes 12VDC SMPS with adjustable output.
Head slap and face palm, I had to lookup "SMPS" to discover it's the
acronym for a switched-mode power supply which I've never heard [the
acronym] before.

I also looked up "Meanwell 12VDC SMPS" and noted they have a large line
of such Power Supply Units (PSUs). :-)

Learn something new every day; thank you!

Thad
Kevin McMurtrie
2014-03-19 04:33:02 UTC
Permalink
Raw Message
Post by Thad Floryan
Post by Kevin McMurtrie
Post by Thad Floryan
[...]
Build a 48 Hour Backup Computer Power Supply - SYSTM
http://youtu.be/jX1OQZ1B6m0
runtime 24:36
Lots of caveats and liability disclaimers in the above video makes
one wonder whether it's even worth doing, but if you want to operate
through a 2-day power outage this is one solution.
And their safety tips should NOT be dismissed or ignored.
May routers run off 9-16 VDC so it's trivial to put them on a battery.
LiFePO4 and lead acid are trivial to charge. LiPo can be float charged
as long as you chose a temperature-compensated voltage that will never
hit 100% charge.
Hi Kevin,
http://en.wikipedia.org/wiki/Polonium
Does its heat boil water into steam turning a generator creating
AC which is then converted to DC in the battery package? :-)
I can handle radioactives safely, but, somehow, I don't think that's
Lithium polymer battery - Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/Lithium_polymer_battery
which seems more suitable for consumers and home use. :-)
Battery types are frequently identified by their primary elements
e.g., NiCd (Nickel-Cadmium), NiMH (Nickel Metal Hydride), Pb (sealed
Lead battery), LiIon (Lithium Ion), AgZn (Silver-Zinc), ZnC/ZnCl2
(Zinc-Carbon/Zinc-Chloride), AgHg (Silver-Mercury button cells),
ZnBr2 (Zinc-Bromine), NaS (Sodium-Sulfur), NaNiCl2 (Sodium-Nickel-
Chloride), and more which is why "LiPo" threw me off. According to
the Wikipedia article, these are the common acronyms for the same
Li-poly, Li-Pol, LiPo, LIP, PLI or LiP
Ugh. "LiP" would be Lithium Phosphorus -- sounds very wicked. :-)
and they're rechargeable and often used in cell phones. Hmmm, my
two current cellphones use Li-Ion batteries. The Wikipedia article
The advantages of Li-ion polymer over the lithium-ion design
include potentially lower cost of manufacture, adaptability to a
wide variety of packaging shapes, reliability, and ruggedness,
with the disadvantage of holding less charge. Lithium-ion
polymer batteries started appearing in consumer electronics
around 1995.
That "less charge" for LiPo bugs me and the reason is "lower cost"
which has a certain negative connotation.
If you've ever seen a Lithium Ion battery go critical, you'd know that
the safer ones are worth the capacity loss. A big UPS-sized Lithium Ion
battery in my house would scare the crap out of me.

LiFePO4 is the most safe. Lithium Polymer Ion is safe against puncture
and shorting, but will otherwise produce flaming electrolyte jets then
become red hot when abused.
Post by Thad Floryan
Post by Kevin McMurtrie
... LiPo can be float charged
as long as you chose a temperature-compensated voltage that will never
hit 100% charge. Meanwell makes 12VDC SMPS with adjustable output.
Head slap and face palm, I had to lookup "SMPS" to discover it's the
acronym for a switched-mode power supply which I've never heard [the
acronym] before.
I also looked up "Meanwell 12VDC SMPS" and noted they have a large line
of such Power Supply Units (PSUs). :-)
Learn something new every day; thank you!
Thad
sms
2014-03-17 14:12:57 UTC
Permalink
Raw Message
Post by Kevin McMurtrie
May routers run off 9-16 VDC so it's trivial to put them on a battery.
LiFePO4 and lead acid are trivial to charge. LiPo can be float charged
as long as you chose a temperature-compensated voltage that will never
hit 100% charge. Meanwell makes 12VDC SMPS with adjustable output.
Yes, those Meanwell SMPS supplies are pretty nice. I'm using a 24VDC
model with adjustable output. "Adjustable output" means a small range of
adjustability, just a couple of of volts in either direction, but that's
sufficient. But if you want to do it properly, you need to have a device
that doesn't over-charge the battery but that switches to full battery
power when it detects an AC failure without bringing the system down.
This is pretty easy when the computer is running off of a single 12V supply.
Loading...