VG224 Line voltage

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Jul 14th, 2009
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The line voltage for all VG224 ports is low (10-11V).

I have change the idle-voltage to high and the impedance to 600r, and it still didn't do any change.

Does anybody know how to solve this problem? i need at least 24 volts to operate my analog phones

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testeven Tue, 07/14/2009 - 09:24
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The VG224 Line voltages are documented at:

The idle-voltage low setting designates -24 V and the idle-voltage high setting designates -48 V.

There's a bug: CSCsc74959 that explains why you can get 37V instead of 48V, but apparently you are still getting a low voltage even though you

set it to high, correct?

Make sure you configured the idle-voltage high under each voice port and try doing a shut/no shut to the port too.

If you measure the voltage how much do you get? and what IOS version are you using?

Hope this helps! If it does, please rate :)



valides007 Tue, 07/14/2009 - 09:44
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i made sure all the ports are configured with idle-voltage high. I also didd shut/no shut on every ports. Still getting a measured voltage of 10V to 11V.

The version is 12.4(6)XE1. The other thing is that i have 2 other units (VG224) configured exactly the same with the same version number and they work fine. Also as i remember this gateway was working fine before

testeven Wed, 07/15/2009 - 16:31
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Can you try using the "no battery-reversal" on the voice-port? And see if this helps?

Dwayne Whitehead Tue, 09/24/2013 - 22:29
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We are facing the same issue, when you set idle-voltage high, it is not showing when you check the running config or do a show voice port..

Any ideas?

We are running an MGCP VG224 Version 12.4(22)T5

Anyone able to fix this? Is it a bug?

Hythim Ali El Hadad Wed, 09/25/2013 - 06:19
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Try this command

vg(config-voiceport)#alt-battery-feed feed2



Adam Hinchliff Thu, 07/09/2015 - 22:19
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We run multiple vg224 and the maximum we can get is 39v on idle-voltage high. As we know vg224 can only go 43v and in order to get that i used alt-battery-feed feed2.



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