120A CSU not working on PRI 3

[marty773]

I have 6 120A CSU's I have tried to use on a PRI circuit into a G650 cabinet, CM 4.0. I get a solid red light on the top of the 464 F card and status light 1 blinks red. I am using a straight through cable and have set the CSU type to integrated on the DS1 board. I have swapped 464F cards, same thing. These do work on circuits that are not PRI.
One of the units was working fine on a test definity switch I used to turn up PRI's.
Is there something I am missing in Communication Manager?
Also, these come up from the smartjack onto a t-1 patch panel. Then patched again to a panel that send it to the comm rack, then into my equipment.
Any help is greatly appreciated.

 

[dufus2506]

Are the cables you're using supplied by Avaya? They have cables that have a definite "Network" and "CSU" end to them. A common ethernet cable may not work.

I'd also be very certain which jack on the CSU you're connecting to. There is one that is configured be dry contacts for an external alarm. Be sure you're not connecting there.

Carpe dialem! (Seize the line!)

 

[dufus2506]

Check this document. It has pinouts of the connectors on a 120A CSU, and the cables it uses.

http://support.avaya.com/edoc/docs/defg1/g1csuin1.pdf

Carpe dialem! (Seize the line!)

 

[dufus2506]

Oh... another thing I'd check would be how many PRI's you have in the system already. You're fairly limited to how many PRI's a system port network can have when it's made up of G650s.

Because of timeslot limitations in an PN, you're limited to no more than 8 T1's in any PN.

Carpe dialem! (Seize the line!)

 

[phonesrus]

The issue you are experiencing may be related to a defective 120A3 ICSU that has damaged your TN464 boards. The boards will still work with Standard Amphenol provisioned T-1/PRI connections, and external CSU/DSU's. There is a QPPCN 1359B, which is no longer published, that refers to 120A3 ICSU's with serial#'s 01DR09xxxxxx thru 02DR04xxxxxx that may/will fail, and if used on other boards, will damage other boards. Extract below.

"QPPCN 1359B 09/17/2002
This change is being issued to replace incorrectly manufactured 120A3 ICSUs which can fail, resulting in an open +5 volt ICSU fuse on the DS1 board. This failure will cause a T1 span loss of signal and failure of DS1-BD test 138.
In the case of a failed ICSU, replacing the DS1 board without first replacing the ICSU will result in another defective DS1 board. Only the +5 volt supply to the ICSU fails, so the DS1 board will function on a T1 span that does not use an ICSU, i.e. no CSU or external CSU. To verify that this problem is present, the DS1 boards +5 volt fuse can be checked for an open circuit across F1. See

http://info.dr.avaya.com/~ldn/TN464/fuse-check.html

for details.
These units should be replaced with 120A2 ICSUs, 120A3 ICSUs with serial numbers of 01DR08XXXXXX or less, 120A3A ICSUs ("A" suffix denotes remanufactured units) with any serial number, or 120A4 ICSUs."

NOTE: The TN464 Boards must be replaced also, they will not work with any ICSU! These defective ICSU's will damage any DS1 board they are connected to, ie: TN767, TN464, TN2313, etc.
The Boards will, however, work with amphenol T-1 cabling and an external CSU with T-1/PRI configuration, that part of the board is not damaged.

 

[mikej97204]

I have a number of 120's and since I use a straight through Cat5 cable on them, I have to use a cross over plug. I have a couple that go through a smart jack that are crossed at the jack and I don't need the cross over plug. If you haven't tried it, try one with a T1 cross over cable or a cross over plug.

I don't know about the G650, but on my G3r and G3si I don't use CSU's any more. I go straight from the back of the switch to the patch jack or patch panel on our DS3's. So far, they work just fine and I've saved a bunch of money on the last 20 T1's I brought up. One of these days I'm going to remove the Acer CSU's and 120's I'm using. I'm always afraid I'm going to snap a 120 off as I work behind and around my G3's.

Mike

 

[Mitch672]

phonesrus, I have replaced many, many, many of those 1A surface mount fuses, it's pretty easy, and the fuses are available from DigiKey. And, yes, a defective CSU WILL blow that fuse, and NO other 120 will work on that card, until the fuse is replaced. The fuse is easy to locate, its near the connector end of the DS1 card, in a corner, it's white and says "1A" on it..



Mitch

AVAYA Certified Expert

 

[marty773]

Thank you everyone for your help. I was using a board with a bad fuse.
Thanks again.