2 Replies Latest reply on Jul 28, 2017 3:06 PM by mhccphoneguy

    What is the maximum loop length for a analog port on the TA-900

    tstrenge New Member

      I have a customer that needs to support a analog phone that is 2500 feet from the siring closet.

        • Re: What is the maximum loop length for a analog port on the TA-900
          jayh Hall_of_Fame

          That's about an 80 ohm loop for 22-gauge and 125 ohms for 24-gauge wire. This should not be an issue at all.

           

          If the wiring goes outside or underground you should consider adding a grounded gas-tube type protector near the TA900 for safety and to avoid potential damage from induced voltage spikes.

           

          P.S. Beware of the stallion in that closet. He tends to kick.

          • Re: What is the maximum loop length for a analog port on the TA-900
            mhccphoneguy New Member

            Dug this tidbit up in my notes from way back....

             

            In most cases the Adtran is within a few feet of the key system, fax, or phone.  This means very low resistance in the wiring.  Low battery is fine, plenty of loop current over a short loop.  In some cases the box may be on a ranch or farm with a long run of wire to a barn half a mile away.  Higher battery is needed to ensure enough current flow to reliably signal off-hook and power the phone at the end of the line.  Auto-battery senses the actual loop current off-hook and adjusts voltage accordingly.

             

            Hope it helps!