Cabinet power supplies

[McGruff753]

Some of you may already be aware of this known issue, but I just experienced it first hand.

I have an Option 11 that lost power to the primary cabinet, but the second cabinet was powered up. Although I was able to re-seat the power supply and bring the system back online, our vendor, NextiraOne, stated the power supply we had, NTAK04AB, was known to have issues.

They replaced the primary cabinet power supply with NTDK78AA. I have opened a ticket to get me second cabinet's power supply changed as well.

 

[Sennback]

sound strange..
we have lots of installations with NTAK04AB, no problems what so ever.
I cant see the need to change the powersupply if it is working.
new powersupplies can be faulty as well..

If the powersupply was working again after you re-seated it, could the problem have occured because you had problems with main power? (temporary dips..)
Do you have batteries? Are they changed after Nortels recommendations?

 

[Avaya911PLM]

Here is the product bulletin on this:

Product Advisory Alert Bulletin: PAA-2003-0318-Global
Issue: 2.0
Date: Sept. 4, 2003

Option 11/11E – NTAK04/05 Power Supply – Update

This bulletin is being updated to add a modification offer under the Recommended Action section and the Modification Ordering Procedure. This bulletin supersedes bulletin PAA-2003-0256- Global.

Nortel Networks has become aware of an issue on early vintages of the NTAK04 and NTAK05 power supplies manufactured between April 1992 and December 1994 that may affect the service life of the supply.

System Configuration: Meridian 1 Option 11, 11E and 11C systems using the NTAK04 and NTAK05 power supply vintages listed below.

Affected Product Code/Vintage:
All affected supplies have the same release 04 printed circuit board on the DC to DC converter (NTAK0403).

Production Vintages
NTAK0403 Rls 04 artwork implemented April 1992 & remained in production until Dec 1994. The upper level packs and vintages produced with this artwork are:

NTAK04AA Release 07 to and including 17 CISPR A supply
NTAK04AB Release 01 to and including 09 CISPR A supply
NTAK04BA Release 01 to and including 08 CISPR B supply
NTAK05AA Release 02 to and including 15 DC only supply

Upgrade Vintages

Repair upgrade paths for the power supply allow the release 04 artwork to be retained in the upgrading of the supplies to the following releases:

NTAK04AA to release 19
NTAK04AB to release 12
NTAK04BA to release 08
NTAK04BB to release 03
NTAK05AA to release 17

Marketing Regions: Global

Problem Description:

It has been found that on the artwork used on the cards listed above, a section of the board under an electrolytic capacitor’s insulator, over a time period of 9 – 12 years may start to deteriorate, creating the potential for a short circuit between two parallel power tracks. This in turn, may result in excessive heat build up under the capacitor insulator to the point where the material in the area may smoke and burn.
This problem does not occur on all boards and where it occurs, may not cause any functional failure of the card. The short may burn itself out and the board continues to function. However, in some cases, the heat damages the card to the point where there is visual damage to the card or there is a secondary failure on the card causing the board to fail. In extreme cases the damage can extend to the backplane at the point where the card’s -48V Aux supply connects to the backplane. Also, because of the varied failure modes, the operation of other cards in the cabinet may be affected and extreme cases, electrical damage to other cards is possible.

Any burning of material should extinguish itself after a few seconds, as the material used in the card will not support combustion on its own. The failure mechanism of this problem has been duplicated in our labs and the test results have been reviewed. Nortel Networks has reviewed its findings with the CSA Audits and Investigation Group and has concluded that no safety concern exists with this failure mode.

Nortel Networks considers this to be a service life affecting problem which should be addressed as part of each site’s preventative maintenance routine.

--
Fletch
Visit the Nortel Technical Support Portal at:

http://www.nortelnetworks.com/support