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New Member

FXS Ring Voltage

Is it possible to set the ring voltage on an VG20X FXS port to 70-75V ?  Or on a VIC-FXS card?   I am trying to interface to a Valcom V 9940 paging unit, and this is what the vendor suggests


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FXS Ring Voltage

Hi Pete,

I have not heard of that requirement before The VG20x does not have any

adjustments for ring voltage. You could try the VIC3-2FXS/DID-E;


The  VIC3-2FXS-E/DID module supports all the voice features that exist on  VIC and VIC2 modules. In addition, the VIC3-2FXS-E/DID module also  supports:

• Mixed FXS and DID ports within the same VIC module

• Higher ringing voltage-65 Vrms (no load)

• Higher loop current 35 mA-to accommodate specialty phones

• Longer loop length-for loops with 26 AWG wire, up to 11,000 feet (3,400 meters)

• Device security-to distinguish between Cisco genuine and non-genuine Cisco modules

• Surge and Transient Protection per Network Equipment Building Standards (NEBS) (GR1089) Level 3 Type 1 and 3



"Show a little faith, there's magic in the night" - Springsteen

FXS Ring Voltage


I've done many Valcom integrations with Cisco gateways.  I've always had success with a VIC2 and VIC3 FXS cards.  I haven't tried it with a VIC card.  I would doubt that the rinking voltage is the issue.  HAve you hooked up a multimeter on AC Voltage during a ring cycle to test the voltage?  I would try that.  I think the issue is more likely the cable or you are connected to the wrong port on the Valcom unit.  Some valcom units only work with FXO cards.


New Member

FXS Ring Voltage

Thanks for the quick response.  The ring voltage issue was suggested by Valcom TS, saying that at least 70-75v is needed.

I am connecting a v9940 to the fxo port.  I get a fast busy, fwiw.  I am not at the site, and wouldnt be able to hook a multimeter to measure ac voltage.  perhaps I will try a fxs port, but it would be off a VG20X gateway