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What are the recommended guidelines when installing FXS Analog Voice Port lines using the VG248 gateway with FXS ports when you consider issues like distance limitations, electrical grounding, or protection from induced currents when lightning occurs.


As far as the distance limitation on the Foreign Exchange Station (FXS) port goes, it has to do with the total allowable loop resistance, incuding the termination equipment and the phone resistance should not be above 600 Ohms.

Refer to the FXS Analog Voice Port Maximum Distance section of Planning Your Installation.

Though this document talks about the VG224, the FXS port specifications should be the same for VG224 and VG248.

Normally it is recommended that the analog lines connecting the FXS port on the gateway should be in the same building where the VG248 is located since the VG248 is not equiped to handle electical grounding issues or protection from induced currents.  If your environment is vulnerable to high currents between the underground wiring, there may be a potential risk of damaging the equipment.

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‎06-22-2009 06:17 PM
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