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Flashing red light on the 2MB PRI Card

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themegalord

Technical User
Mar 3, 2006
63
US
Dear All,

I just setup a Meridian Option 11C and tied it to an Avaya PBX. Everything seems to be working fine, but the red (major) alarm is constantly flashing with a corresponding cracking sound on the telephone.

After all while, the constant flashing now results in OOS alarm and the trunk goes down. The technician on site tells me that he has to power-cycle the PBX before the card comes back up again.

Can someone please tell what the problem is? Is it the microwave radio link between the two PBXs, is it the clocking settings on the Nortel?, is it the clocking settings on the Avaya? or is the card faulty?

Please let me know.

Sincerely yours,
megalord
 
The LEDS on the NTAK79 2MB PRI card are:

OOS
ACT
RED
YEL
LBK
CC
DCH

Which one is flashing?

If it is the RED a red alarm state has been detected. This represents a LOCAL alarm state of:
Loss of Carrier (LOS)
Loss of Frame (LFAS), or
Loss of CRC Multiframe (LMAS)


--
Fletch

Nortel Emergency Services PLM

Don't forget about the FREE E911 Webinar Oct. 30th!
Register online at
 
It's the RED one that's flashing. But it doesn't flash bright red, just faintly but continuous. During this stage incoming and outgoing calls can go through the trunk. But then, after a period of time, the OOS light comes on and stays on. What could possibly be the problem?
 
Are you getting any errors on the system? Other than a faulty card, it may be a poor signal coming in.

Are you using coax or twisted pair cable for the E1 connection?

How long is the run between the card and the microwave gear?

I would suggest:
Look for error on the system TTY
Confirm the cable is in good shape - connections are tight
Check the Dip switches for correct settings
Swap with a known good card


--
Fletch

Nortel Emergency Services PLM

Don't forget about the FREE E911 Webinar Oct. 30th!
Register online at
 
The cables seem to be fine. If the microwave technician gives me a loopback from the microwave radio back to the option 11c mini, all the alarms are cleared. This should mean that all the connections are good.

But if he gives me a loop all the way from the far-end microwave radio, the red light keeps blinking. The microeave guys keeps telling me to check my clocking parameters.

What do you think?
 
Excellent troubleshooting. I have seen similar issues with a user doing a link from the US to Peurto Rico. The carrier gear was injecting clocking signal that was disrupting the circuit. I would focus there.

If you loop towards the Avaya do they see issues?

--
Fletch

Nortel Emergency Services PLM

Don't forget about the FREE E911 Webinar Oct. 30th!
Register online at
 
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