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ejansson
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RB 333 not working on long cable run

Sat Nov 03, 2007 5:14 pm

Has anyone seen or found a solution for this problem. We have a 300ft tower and the cable run is at the limits for Ethernet. We have 4 Rb532 working fine. We put in a RB333 for the final AP and can not get it to boot or give us a link lite on the switch. I have tried 18 and 24v supplies...... Hey MT... please go to all 48v supplies for the big boards!


Erik
 
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Re: RB 333 not working on long cable run

Sun Nov 04, 2007 1:33 pm

ejansson -
We have a 285 foot run.... I use a 28vdc supply w/2 XR5s in the RB333. Seems to work fine. I don't have the calculator link handy but you can find one on the web concerning wire resistance and voltage drop on a 24 guage wire / CAT5E. Remember that the POE for this uses two 24 guage wires for each side of the DC supply so be sure to use that when you are figuring out your voltage drop/current capacity of the CAT5E cable.

** Disclaimer **
Use this information at your own peril - MT will not cover a board damaged by an overvoltage condition!! Neither will I !! I am only telling you that it works for me - not that it will work for anyone / everyone!
** End Disclaimer **

And I agree about the 48vdc supply - I wish they were all 48vdc but I can live with high power boards being 48vdc and the 'lower' powered boards at 24vdc - let's just be consistant so we don't have to buy 14 different power supplies.....
Thom Lawless
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RapidWiFi, LLC
thom.lawless [at] rapidwifi.com
 
tully
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Re: RB 333 not working on long cable run

Mon Nov 05, 2007 11:33 am

The power supply (block or wallwart) needs to have enoght AMPs for the high power cards.
 
ejansson
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Re: RB 333 not working on long cable run

Mon Nov 05, 2007 6:03 pm

Current should not be an issue. The PSU are the same I have been using for the RB532 and deliver around 18-20 watts. So unless the 333 is a power pig compared to the 532 I should be fine. I have not seen any power consumption ratings for the 333 so I would be interested to know what they are.


Erik
 
ericsooter
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Re: RB 333 not working on long cable run

Tue Nov 06, 2007 6:26 am

Tully is right. The power supply will need to handle the amps. A 48V/500mA PS can handle 24Watts. But a 24V/500mA PS can only handle 12 Watts. I do think that the 333 has a bit more consumption than the 532.
 
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BrianHiggins
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Re: RB 333 not working on long cable run

Wed Nov 07, 2007 2:14 am

The power supply (block or wallwart) needs to have enoght AMPs for the high power cards.
agree'd, but it would still really be nice if all of "The RouterBOARD power series" were 48v 802.3af compliant for both standard and passive PoE, allowing us the ability to power them using our choice of power supplies.
 
richard_s
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Re: RB 333 not working on long cable run

Wed Nov 07, 2007 3:58 pm

i have spliced the dc output from fhe mains transformer and extended it using heavy duty speaker cable. it works fine on my AP's its cheaper than using POE.

richard

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