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mcdaddyg
New Contributor

T1 / PRI port will not link to Phone System

I am replacing a telco PRI with a SIP PRI.  The telco is working fine.  When we plug the PRI line from the telco into the TA916e port T1, it does not connect.  The PBX is looking for ESF; B8ZS; NI2; 5ESS.  I have tried every configuration combination on the physical interface to no avail.  I have the configuration attached.  I also updated the firmware to the latest version on the website as well.

Baffled and Frustrated!

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Re: T1 / PRI port will not link to Phone System

First, if the TA916e T1 port LED does not go Green, then try rolling the T1 cable Transmit and Receive pairs.  Per the TA900e Hardware Installation Guide, the T1 pinouts are:

- PIN 1 - R1 - Receive data from the network (Ring 1) - Orange / White

- PIN 2 - T1 - Receive data from the network (Tip 1) - Orange

- PIN 4 - R - Transmit data towards the network (Ring) - Blue

- PIN 5 - T - Transmit data towards the network (Tip) - Blue / White

Change "one" end of the cable to:  PIN 1 - Blue, PIN 2 Blue / White, PIN 3 Orange / White, PIN 4 Orange.

 

Second, I have never had to change the T1 FDL command, try setting it back to defaults with "fdl ansi".  The T1 is configured as ESF / B8ZS, which has an FDL by default.  The ISDN PRI needs 64Kbps per DSO, so the TELCO PRI should also be ESF / B8ZS.

 

Third, if you are connecting a TELCO PRI to the TA916e, then the "interface pri 1" provisioning has to change roles.  Use "role user" to make this port look like customer premise equipment to the TELCO.  If the TA916e port is connected to a PBX's ISDN PRI interface, then the TA916e PRI must look like the "network" to the PBX, that is when you would use "role network".

Hope this helps.