Hi All! I've been discussing possibility of using USB port on 2011/951 series to power up a modem like TP-link 8816 which uses 5v power supply using a cable like this: http://miniimg2.rightinthebox.com/images/384x384/201403/ljhnpo1394624693508. jpg I checked with MT engineering team, and received promising response: "The minimum output current both models can provide is 500mA. RB951Ui-2HnD and RB2011 with wireless should be able to supply even up to 1A of output current. RB2011 without wireless should be able provide up to 2A output current. Only note that we guarantee the minimum output current" So TP-Link ships with a 5v/1A power supply and so assuming that the device actually consumes 'up to 1A' then perhaps routerBoards able to supply 'up to 1A' might actually work as a pair. Although I'm thinking that the power consumption will increase as packet throughput increases on both, then perhaps as the transfer load ramps up, power available to the modem may be constrained, and so might cause trouble under load. So I find myself wondering whether someone else may have already been own this path and so if you have, and are willing to share your observations, I'm most curious as to how it turned out! :-) Cheers! Mike.
Have a look here: https://en.wikipedia.org/wiki/USB#Power The USB 1 and 2 specification calls for consumption to be 500mA at down to 4.5V (4.5V allows for some cable loss under load). A USB1/2 device should draw no more than 500mA. Typically you will find modems with 5V supplies at 1A or 2A. If it's minimalist modem-only device you might find it never draws more than 500mA at 5V in spite of having a 1A supply. You'll really need to get a multimeter/ammeter in the path to see just how much current is really drawn by the device under full load at 5V to be sure. On 6 October 2015 at 09:57, Mike Everest <mike@duxtel.com> wrote:
Hi All!
I've been discussing possibility of using USB port on 2011/951 series to power up a modem like TP-link 8816 which uses 5v power supply using a cable like this:
http://miniimg2.rightinthebox.com/images/384x384/201403/ljhnpo1394624693508. jpg
I checked with MT engineering team, and received promising response:
"The minimum output current both models can provide is 500mA. RB951Ui-2HnD and RB2011 with wireless should be able to supply even up to 1A of output current. RB2011 without wireless should be able provide up to 2A output current. Only note that we guarantee the minimum output current"
So TP-Link ships with a 5v/1A power supply and so assuming that the device actually consumes 'up to 1A' then perhaps routerBoards able to supply 'up to 1A' might actually work as a pair.
Although I'm thinking that the power consumption will increase as packet throughput increases on both, then perhaps as the transfer load ramps up, power available to the modem may be constrained, and so might cause trouble under load.
So I find myself wondering whether someone else may have already been own this path and so if you have, and are willing to share your observations, I'm most curious as to how it turned out! :-)
Cheers!
Mike.
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
--
Hi Jason, thanks for your comments! That is all very well, but we are not expecting to power the modem by its USB port - in fact the modem does not support powering over USB cable {which adds to my uncertainty whether the result will be stable :-} The concept we are working on is to use a USB cable that simply takes the 5v power from the cable and terminate in a barrel plug to fit the modem power socket ;) Since the 8816 is a really bare-bones basic unit, then I feel mildly optimistic that it will (as you also suspect) much less than the spec of the power supply. So I'm keen to hear whether the concept is worth testing. The other fellow who I've been discussing this with is also on this list, and has indicated that he intends to source a suitable cable and give it a go. But if someone else who has already tried it can say without a doubt that it's doomed to failure, then maybe we can save a bit of heartache! :-D Cheers! Mike.
-----Original Message----- From: Public [mailto:public-bounces@talk.mikrotik.com.au] On Behalf Of Jason Hecker (Up & Running Tech) Sent: Tuesday, 6 October 2015 10:07 AM To: MikroTik Australia Public List <public@talk.mikrotik.com.au> Subject: Re: [MT-AU Public] power routerboard and modem with one supply
Have a look here:
https://en.wikipedia.org/wiki/USB#Power
The USB 1 and 2 specification calls for consumption to be 500mA at down to 4.5V (4.5V allows for some cable loss under load).
A USB1/2 device should draw no more than 500mA.
Typically you will find modems with 5V supplies at 1A or 2A. If it's minimalist modem-only device you might find it never draws more than 500mA at 5V in spite of having a 1A supply. You'll really need to get a multimeter/ammeter in the path to see just how much current is really drawn by the device under full load at 5V to be sure.
On 6 October 2015 at 09:57, Mike Everest <mike@duxtel.com> wrote:
Hi All!
I've been discussing possibility of using USB port on 2011/951 series to power up a modem like TP-link 8816 which uses 5v power supply using a cable like this:
http://miniimg2.rightinthebox.com/images/384x384/201403/ljhnpo139462469 3508.
jpg
I checked with MT engineering team, and received promising response:
"The minimum output current both models can provide is 500mA. RB951Ui-2HnD and RB2011 with wireless should be able to supply even up to 1A of output current. RB2011 without wireless should be able provide up to 2A output current. Only note that we guarantee the minimum output current"
So TP-Link ships with a 5v/1A power supply and so assuming that the device actually consumes 'up to 1A' then perhaps routerBoards able to supply 'up to 1A' might actually work as a pair.
Although I'm thinking that the power consumption will increase as packet throughput increases on both, then perhaps as the transfer load ramps up, power available to the modem may be constrained, and so might cause trouble under load.
So I find myself wondering whether someone else may have already been own this path and so if you have, and are willing to share your observations, I'm most curious as to how it turned out! :-)
Cheers!
Mike.
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com. au
-- _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
Hi Mike, I understand what is it you are trying to do with USB->barrel. As Mikrotik only guarantee 500mA but feel confident about 1A (wink wink) you may well get away with it. Try rig up a multimeter in ammeter mode and see just how much power the modem draws when transferring data at 20/1Mbit - only then can you be confident the RB2011 and modem will work fine under load. On 6 October 2015 at 10:14, Mike Everest <mike@duxtel.com> wrote:
Hi Jason, thanks for your comments!
That is all very well, but we are not expecting to power the modem by its USB port - in fact the modem does not support powering over USB cable {which adds to my uncertainty whether the result will be stable :-}
The concept we are working on is to use a USB cable that simply takes the 5v power from the cable and terminate in a barrel plug to fit the modem power socket ;)
Since the 8816 is a really bare-bones basic unit, then I feel mildly optimistic that it will (as you also suspect) much less than the spec of the power supply. So I'm keen to hear whether the concept is worth testing. The other fellow who I've been discussing this with is also on this list, and has indicated that he intends to source a suitable cable and give it a go. But if someone else who has already tried it can say without a doubt that it's doomed to failure, then maybe we can save a bit of heartache! :-D
Cheers!
Mike.
-----Original Message----- From: Public [mailto:public-bounces@talk.mikrotik.com.au] On Behalf Of Jason Hecker (Up & Running Tech) Sent: Tuesday, 6 October 2015 10:07 AM To: MikroTik Australia Public List <public@talk.mikrotik.com.au> Subject: Re: [MT-AU Public] power routerboard and modem with one supply
Have a look here:
https://en.wikipedia.org/wiki/USB#Power
The USB 1 and 2 specification calls for consumption to be 500mA at down to 4.5V (4.5V allows for some cable loss under load).
A USB1/2 device should draw no more than 500mA.
Typically you will find modems with 5V supplies at 1A or 2A. If it's minimalist modem-only device you might find it never draws more than 500mA at 5V in spite of having a 1A supply. You'll really need to get a multimeter/ammeter in the path to see just how much current is really drawn by the device under full load at 5V to be sure.
On 6 October 2015 at 09:57, Mike Everest <mike@duxtel.com> wrote:
Hi All!
I've been discussing possibility of using USB port on 2011/951 series to power up a modem like TP-link 8816 which uses 5v power supply using a cable like this:
http://miniimg2.rightinthebox.com/images/384x384/201403/ljhnpo139462469 3508.
jpg
I checked with MT engineering team, and received promising response:
"The minimum output current both models can provide is 500mA. RB951Ui-2HnD and RB2011 with wireless should be able to supply even up to 1A of output current. RB2011 without wireless should be able provide up to 2A output current. Only note that we guarantee the minimum output current"
So TP-Link ships with a 5v/1A power supply and so assuming that the device actually consumes 'up to 1A' then perhaps routerBoards able to supply 'up to 1A' might actually work as a pair.
Although I'm thinking that the power consumption will increase as packet throughput increases on both, then perhaps as the transfer load ramps up, power available to the modem may be constrained, and so might cause trouble under load.
So I find myself wondering whether someone else may have already been own this path and so if you have, and are willing to share your observations, I'm most curious as to how it turned out! :-)
Cheers!
Mike.
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com. au
-- _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
--
I would definitely check the current draw on the 8816. When we had the storms earlier in the year, I quickly threw a 7805 (with a 10cm*10cm copper board as a heatsink) onto the 24v output of my APC DC UPS that powers my CRS109, and plugged that into my 8817. It runs fine, but the 7805 is ~40C when there is no traffic, and hits 75C while downloading linux ISO's. Which would suggest that it's pulling far more than the 500mA that USB will want to provide. I'd test it myself, but I gave the 8817 up as a bad joke, and went back to a Cisco 877 in bridge mode so I could control the SNR margin to get some stability on the line. :) FTTN ordered today, so not much longer on ADSL. Hoping that fixes our constant dropouts! On 6 October 2015 at 09:57, Mike Everest <mike@duxtel.com> wrote:
Hi All!
I've been discussing possibility of using USB port on 2011/951 series to power up a modem like TP-link 8816 which uses 5v power supply using a cable like this:
http://miniimg2.rightinthebox.com/images/384x384/201403/ljhnpo1394624693508. jpg
I checked with MT engineering team, and received promising response:
"The minimum output current both models can provide is 500mA. RB951Ui-2HnD and RB2011 with wireless should be able to supply even up to 1A of output current. RB2011 without wireless should be able provide up to 2A output current. Only note that we guarantee the minimum output current"
So TP-Link ships with a 5v/1A power supply and so assuming that the device actually consumes 'up to 1A' then perhaps routerBoards able to supply 'up to 1A' might actually work as a pair.
Although I'm thinking that the power consumption will increase as packet throughput increases on both, then perhaps as the transfer load ramps up, power available to the modem may be constrained, and so might cause trouble under load.
So I find myself wondering whether someone else may have already been own this path and so if you have, and are willing to share your observations, I'm most curious as to how it turned out! :-)
Cheers!
Mike.
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
-- Damien Gardner Jnr VK2TDG. Dip EE. GradIEAust rendrag@rendrag.net - http://www.rendrag.net/ -- We rode on the winds of the rising storm, We ran to the sounds of thunder. We danced among the lightning bolts, and tore the world asunder
Oh, 24V to 5V is a massive drop for a 7805! As you may be aware you are washing off 19V * (at least) 0.5A which means more than 9.5W being dumped into the heatsink. On 6 October 2015 at 10:17, Damien Gardner Jnr <rendrag@rendrag.net> wrote:
I would definitely check the current draw on the 8816. When we had the storms earlier in the year, I quickly threw a 7805 (with a 10cm*10cm copper board as a heatsink) onto the 24v output of my APC DC UPS that powers my CRS109, and plugged that into my 8817. It runs fine, but the 7805 is ~40C when there is no traffic, and hits 75C while downloading linux ISO's. Which would suggest that it's pulling far more than the 500mA that USB will want to provide.
I'd test it myself, but I gave the 8817 up as a bad joke, and went back to a Cisco 877 in bridge mode so I could control the SNR margin to get some stability on the line. :)
FTTN ordered today, so not much longer on ADSL. Hoping that fixes our constant dropouts!
On 6 October 2015 at 09:57, Mike Everest <mike@duxtel.com> wrote:
Hi All!
I've been discussing possibility of using USB port on 2011/951 series to power up a modem like TP-link 8816 which uses 5v power supply using a cable like this:
jpg
I checked with MT engineering team, and received promising response:
"The minimum output current both models can provide is 500mA. RB951Ui-2HnD and RB2011 with wireless should be able to supply even up to 1A of output current. RB2011 without wireless should be able provide up to 2A output current. Only note that we guarantee the minimum output current"
So TP-Link ships with a 5v/1A power supply and so assuming that the device actually consumes 'up to 1A' then perhaps routerBoards able to supply 'up to 1A' might actually work as a pair.
Although I'm thinking that the power consumption will increase as packet throughput increases on both, then perhaps as the transfer load ramps up, power available to the modem may be constrained, and so might cause
http://miniimg2.rightinthebox.com/images/384x384/201403/ljhnpo1394624693508 . trouble
under load.
So I find myself wondering whether someone else may have already been own this path and so if you have, and are willing to share your observations, I'm most curious as to how it turned out! :-)
Cheers!
Mike.
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
--
Damien Gardner Jnr VK2TDG. Dip EE. GradIEAust rendrag@rendrag.net - http://www.rendrag.net/ -- We rode on the winds of the rising storm, We ran to the sounds of thunder. We danced among the lightning bolts, and tore the world asunder _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
--
I had toyed with the idea of getting a POE powered DSL modem made in china. Figured that currently, they are USB <-> Ethernet <-> DSL, no reason that you couldn't skip the USB part. The RB2011 with ether10 and POE out would be the perfect place for it. -----Original Message----- From: Public [mailto:public-bounces@talk.mikrotik.com.au] On Behalf Of Mike Everest Sent: Tuesday, 6 October 2015 8:58 AM To: 'MikroTik Australia Public List' <public@talk.mikrotik.com.au> Subject: [MT-AU Public] power routerboard and modem with one supply Hi All! I've been discussing possibility of using USB port on 2011/951 series to power up a modem like TP-link 8816 which uses 5v power supply using a cable like this: http://miniimg2.rightinthebox.com/images/384x384/201403/ljhnpo1394624693508. jpg I checked with MT engineering team, and received promising response: "The minimum output current both models can provide is 500mA. RB951Ui-2HnD and RB2011 with wireless should be able to supply even up to 1A of output current. RB2011 without wireless should be able provide up to 2A output current. Only note that we guarantee the minimum output current" So TP-Link ships with a 5v/1A power supply and so assuming that the device actually consumes 'up to 1A' then perhaps routerBoards able to supply 'up to 1A' might actually work as a pair. Although I'm thinking that the power consumption will increase as packet throughput increases on both, then perhaps as the transfer load ramps up, power available to the modem may be constrained, and so might cause trouble under load. So I find myself wondering whether someone else may have already been own this path and so if you have, and are willing to share your observations, I'm most curious as to how it turned out! :-) Cheers! Mike. _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
Hi, I run the 8817 from the 2011 usb port using a similar cable for more than 6 months. Current draw is 350-650mA depending on download. 600mA+ monitored with constant 15mbps 30 min download and the 2011 gets hot. As this is in the lab we want to test 2011 reliability. Noticed the 2011 lockup on 2 occurs but not sure if this was due to firmware at the time. Since going with the stable firmwares we got no lockups. Cheers /K On 10/06/2015 09:57 AM, Mike Everest wrote:
Hi All!
I've been discussing possibility of using USB port on 2011/951 series to power up a modem like TP-link 8816 which uses 5v power supply using a cable like this:
http://miniimg2.rightinthebox.com/images/384x384/201403/ljhnpo1394624693508. jpg
I checked with MT engineering team, and received promising response:
"The minimum output current both models can provide is 500mA. RB951Ui-2HnD and RB2011 with wireless should be able to supply even up to 1A of output current. RB2011 without wireless should be able provide up to 2A output current. Only note that we guarantee the minimum output current"
So TP-Link ships with a 5v/1A power supply and so assuming that the device actually consumes 'up to 1A' then perhaps routerBoards able to supply 'up to 1A' might actually work as a pair.
Although I'm thinking that the power consumption will increase as packet throughput increases on both, then perhaps as the transfer load ramps up, power available to the modem may be constrained, and so might cause trouble under load.
So I find myself wondering whether someone else may have already been own this path and so if you have, and are willing to share your observations, I'm most curious as to how it turned out! :-)
Cheers!
Mike.
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
participants (5)
-
Damien Gardner Jnr -
Jason Hecker (Up & Running Tech) -
Kilburn Abrahams -
Mike Everest -
Tim Warnock