9115 remote office units cutting off

[jsty]

we have several M9115 units connecting to the RLC's via PSTN over home users POTS lines and inbound PRI to the switch. The 9115's are set to call the DN of the data TN that corresponds to their remote voice tn. Their inbound POTS call comes into the pbx on our normal PRI DID's.

These are acd users and lose their connectivity to the RLC intermittantly throughout the day ? The cards are set up for permanent not on demand. Something in the PRI is causing these connections, nothing more than modem to modem essentially, to tear down. Any ideas?

Thanks

 

[janaya]

Here is what I found on this problem.

Hope this helps.

Title:
PSTN connectivity between RLC and 911x fails.

Facts:
MRO 9115
Nortel Remote Gateway 9115
Remote Office 9115
RLC
PSTN
Analog line
9115 connects via IP, and operates properly.

Symptoms:
PSTN connectivity between RLC and 911x fails.
RLC rejecting call from 9115 modem.
RLC not providing answer tone when called from a phone.

Changes:
Adding PSTN fall-back to 9115.

Cause:
Configuration error.

Fix:

1. Confirm a TN for the Network Port is configured correctly, an example is in the Remote Office Installation Testing - Job Aide v2.0, Appendix F · PBX TN Programming Examples available from

http://www.nortelnetworks.com.

2. Confirm the DN for that TN has been entered in the PSTN Number field of the Network Port Configuration window.

3. Confirm at least one DSP Load field contains 911X and a V32 Compression Algorithm is available.

4. Test by phoning the DID number assigned to the TN, a modem answer tone should be heard.

5. Confirm the Remote Connection Configuration:
a. PSTN must be enabled.
b. Dedicated PSTN n/w Port must contain the number of the Network Port configured above.
c. PSTN Number should contain the phone number of the line the 9115 will be calling from, this benefits the administrator, does not affect performance.
d. Callback for PSTN must be Disable.

6. Test by disabling the IP and attempting to place a call or reset power to the 9115. It may help to enable Modem Tones on the 9115 System Configuration window, causing the modem tones to be heard through the phones speaker if a call is not in progress. The 9115 should dial the DID number, receive answer tone, retrain and begin passing data. Once the modem connection is established, the phone should work normally.

 

[janaya]

Also found this, but good luck getting the LEC to check line noise.

Title:
PSTN connectivity between RLC and 911x fails

Facts:
Remote Office

RLC

9115

1.03.05

PSTN connectivity between RLC and 911x

Programming is correct

9115 connected to a Central Office POTS line

9115 connected to an analog port on the same PBX works fine



Symptoms:
PSTN connectivity between RLC and 911x fails

9115 needs to dial out multiple times to connect to RLC



Cause:
POTS line has large amounts of line noise.



Fix:

The Remote Office 9110 NTDR76BA Release 2 and the Remote Office 9115 NTDR77BA Release 2 has a hardware problem as outlined in Product Bulletin PB-2002-107. If you have hardware of this vintage, it can be returned for repair as outlined in the Product Bulletin.

If you have release 3 or higher hardware and 1.3.5 firmware, the line quality is the prime suspect. Call in a ticket with the local provider of the POTS line and get it repaired.

Residential phone lines greatly vary in quality.
The table below has been generated from North American guidelines and the corresponding CO.
When problems are experienced in having a 9110 or 9115 connect over PSTN · with the symptom
being that it connects and then drops, the POTS line should be tested. Have the technician perform
o Power Influence · reported in dBmC is the effect of 60 Hz AC EMI on the line
o Line length in feet or meters · ensure that the line length is the copper line length, not the
distance to the CO. There could be a line concentrator on a telephone pole half way to the CO
o Line resistance (DC Ohm reading) · have a short placed at the CO and measure from the

Parameter Min Max Troubleshooting Steps:

Line Loss 0 dB -8.5dB > 10dB is considered very poor
Noise Level 0 dBrnC 20 dBrnC >30 dB is considered poor
Power Influence 0 dBmC 80 dBmC > 90 dBmC is considered poor
Balance 60 dB or more ideal IF noise and Power Influence are ok.
On Hook V -48 VDC -54 VDC Must be between values
Off Hook V -8 VDC -12 VDC Must be between values
Loop Current 20 mA Off hook current performance.

 

[jsty]

thanks for the reply, exausted most of those and more. We don't use IP at all. Units get connected 1st time every time fine. Its just that they don't stay connected. If the call comes in on PRI, its just a matter of time before they lose their connectivity.

 

[janaya]

could be line noise on the POTS. I know that will be hard to check with your local LEC. Especially if they are able to talk on the line with no apparent noise.

John