Smart-UPS VT 10 kVA: A Weak Battery Exists

[Anonymous user]

Our Smart-UPS VT 10 kVA: ran a scheduled weekly self test, the test failed with 'A weak battery exists', contacted our UPS maintenance company who sent tech to site, he tested and could not fine the weak battery, in fact he said it was all good (waiting on report from tech who did the testing).  we're still getting the alert every 2 minutes though for weak battery and self test failed ??, below are the SNMP traps being generated.  Anyone seen this before?  Tech thinks it may well be system generated alert has been triggered after X amount of time, UPS has been in production for about 2 years 8 months.

snmpTrapEnterprise = PowerNet-M​IB:apc
experimental.1057.1.0 = 10.9.128.2​51
sysUpTime = 354 days 21 hours 36 minutes 55.30 seconds
snmpTrapOID = PowerNet-M​IB:apc.0.3
mtrapargsString = UPS: Self-Test Failed

snmpTrapEnterprise = PowerNet-M​IB:apc
experimental.1057.1.0 = 10.9.128.2​51
sysUpTime = 354 days 21 hours 36 minutes 52.80 seconds
snmpTrapOID = PowerNet-M​IB:apc.0.7​7
mtrapargsInteger = 36
mtrapargsString = UPS: A weak battery exists.

[BillP]

Paul,

When the tech was on site did he run a self-test and if so did it fail? If he did not run a self-test I suggest doing so to see if the error clears. You can run the self-test via the NMC. 

[MarkC_apc]

My experience with the SURT 10kVA is that if there is one bad battery in any of the four cages (out of a total of 32 batteries!), it will fail the "load" test upon startup.  The "VT" series is advertised to have more "intelligent" charging system - it is possible that it can determine if any of the (many) batteries are about to fail.  Just checking voltages of the battery cages will not indicate a single (or more) bad batteries due to "surface" charge.  There must be some type of "load" test.  Check how the technician did the test and the results.

[Anonymous user]

Thx Bill, ran the self-test via NMC and it failed.  Looks like the default setup is that a notification is generated every 2 minutes until problem is fixed, do you if you can stop the alarm notification ?

26-Jul-16	10:50:41	UPS: Self-Test Failed
26-Jul-16	10:26:24	System: NTP update successful.
26-Jul-16	09:57:23	UPS: Started a self-test.

[Anonymous user]

Thx Mark,  Trying to get the test info still, do you know if there is anyway from the NMC that this information can be found, doesn't seem to be and can't find anything on-line neither.

[BillP]

Hi Paul,

RE: Alarm configuration.

From the NMC you can go to

Configuration > Notification > Event Actions > By Event

Click on “Diagnosis” Then click on “UPS: Self-Test Failed”

Here you can change the settings as required.

RE: Logs

If you require the log data, from the NMC click on About > Support

Here you will have the option to Generate Logs, once generated you can download the logs as a zip file.

Regards,

Rich...

[MarkC_apc]

On 7/25/2016 9:50 PM, paul said:

 Trying to get the test info still, do you know if there is anyway from the NMC that this information can be found, doesn't seem to be and can't find anything on-line neither.

I've only had experience with the SURT line of UPSs.  However, it does appear that the battery cages in your unit are similar in that there are 8 batteries in series in each "cage".  Rather than the smaller 5.5 AH batteries - the replacements for your unit appear to be the 7 AH size (can be up to 9 AH).  They also all appear to be in series.  Bottom line, if any one of these batteries is weak and/or any of the 6 cells in each battery has failed, the entire "cage" will likely cause some type of alarm/failure of the UPS to either start-up or run properly.  The SURT line of UPSs (nor SU/SUA/SMT/SMX) do not have any reporting information from the NMC on actual battery "health".  The logging information can be used to determine if the batteries have lost capacity as the NMC gives detailed information on wattage, time and battery voltage, which can be used to estimate watt-hrs capacity of the batteries.   Again, the "VT" line may have some additional "intelligence" in this area?

I'd think that a good technician would be able to determine this for you, so that you could decide on purchasing new batteries, or if it is another issue.

[Anonymous user]

Thanks for your reply mark. Eventually I rang Schneider and found out you can't get any info out of the NMC to see what battery is causing the issue but I have been told you can from the Front Control Panel doing:

From front control on UPS

select main menu

select faults or diagnostics

select battery (This should tell you which battery is generating the alert)

I haven't done this yet as I'm not based at the site but will get someone tomorrow to do it, find out then.

[MarkC_apc · Accepted solution]

On 7/27/2016 2:57 AM, paul said:

select battery (This should tell you which battery is generating the alert)

Your battery cages must have some "intelligence" built in to the logic.  If the topology of the "VT" line of UPSs is similar the larger SURTS, at least 4 battery cages are required to supply the voltages needed to operate on batteries.  I am able to measure the differences in voltage drops of each cage under load to determine if one cage is bad.  However, for most users, when batteries start going bad due to age or excessive usage, the entire set of cages are generally replaced - that may by your case.  If they are relatively new, hopefully one cage can be replaced under warrantee as it was likely defective from the start.

Hope this helps your decisions,

Mark