Conference netcad::hub_mgnt

3539.0. "DECagent 90 High Failrure Rate ??" by GIDDAY::STANISLAUS () Mon May 20 1996 03:28

	
	
	I have received 4 failed DECagent 90 units from remote sites. This 4 is
out of 16 that failed in the last 6 months. I vaguely recall reading an article
either in TIMA STARS or HUB notes conference (can't seem to find that article
now), which states that there is a problem with version D03 of DECagent 90s,
where the Agent will communicate fine to the console terminal - can set and show
IP address and Gateway address, but the Agent will fail to communicate with the
Ethernet and hence ping to the Agent will fail. I also recall that article 
saying that the fault was due to a failed DC converter (may be inverter). I also
recall the article saying that Agents at rev E01 and above do not see this kind
of failure.

	I have with me our (CSC's - Customer Support Centre's) DECagent 90
that works fine. I wish to swap this good one's DC converter to the above
4 units one at a time and see if they all spring back to life and speak on the
Ethernet. But I don't know how to identify this DC coverter. Is it the big black
component that says "ri Reliablity 20-32787-01 2SA10-10 S-PAC Made in COSTA 
RICA". This way I can prove the same component has failed on all the units or
not.

	The component next to the above  is 29 760171 01 -  is that the Ethernet
Coupling Transformer.

	The component DP8392CN-2 - is that the Ethernet Transceiver Chip.

	It is hard to troubleshoot these without a print set. Is there one 
available on the network.

	Details of the 4 failed agents I have:

	DECagent Number 1:
	PN - DENMA-M
	REV  D03
	SN - AS42105815
	Board P/N 54-20924-01, REV B02,  S/N AS42005017

	DECagent Number 2:
	PN - DENMA-M
	REV  D03
	SN - AS41705746
	Board P/N 54-20924-01, REV B02,  S/N AS40904430

	DECagent Number 3:
	PN - DENMA-M
	REV  D03
	SN - AS41605334
	Board P/N 54-20924-01, REV B02,  S/N AS40904539

	DECagent Number 4:
	PN - DENMA-M
	REV  D03
	SN - AS42105808
	Board P/N 54-20924-01, REV B02,  S/N AS42005019

	Agents 1,2,3 failed in such a way that they can communicate with the
Console Terminal, but Agent 2 failed with DC power LED and all other LEDs OFF 
- i.e. totally dead. As I said 16 units failed for one customer in 6 months 
out of 24 that he has. 

	I have CLD'd this call. But I still wish someone to tell me which is the
DC converter that drives the Ethernet Chip and which chip is the Ethernet Chip
on the board.
 
Alphonse