Symmetra - maint. bypass - should pwr modules be running & capacity showing

[Anonymous user]

I have a 16kva symmetra that is currently in maintenance bypass. (failed MIM but it was replaced and now working again)
I would like to switch out of maintenace bypass mode but I would like to make sure everything works and the UPS doesn't drop the load.
Are the power modules supposed to be running? currently they are not.
All 4 power modules are showing "Off & OK"
Battery stats are as follows:
Battery Capacity: 000.0 %
Runtime Remaining: 0 minutes
Nominal Battery Voltage: 120.0 VDC
Actual Battery Bus Voltage: 023.6 VDC
Battery Frame Status

Frame Status Bad Good Total Vacant
Main OK 0 0 0 4
Total 0 0 0 4

When I turn off the maintenance bypass switch, will these power modules start up and the batteries show as good? I have never put this UPS in/out of maintenance bypass mode before.

Thanks

[BillP]

Hello Gmermuys,

I think I can help you understand exactly what the Symmetra is doing at this time.

Off and OK means that the Power Module's inverter is OFF, but other components such as the charger and PFC could be on (if they are, the fans will spin). If the Power Module fans are not spinning, which I assume they are not, this is not a problem with the Power Modules.

The reason the Power Modules' fans are not spinning is due to your exceptionally dead SYBATT battery modules. I can only assume that those battery modules were left engaged in the frame for a long period of time while the UPS was in maintenance bypass, and otherwise not operating normally. Battery modules must always be disengaged from the frame any time the UPS is not operating normally, otherwise they will discharge beyond recoverable levels. The UPS does not recognize any batteries installed due to the very low (24vDC) battery voltage. Batteries must be over 90v to be recognized, as that is the point where the Power Modules are able to start from an OFF state.

Those SYBATT modules are destroyed and will need to be recycled in accordance with local regulations. You will need at least one good SYBATT module installed in the Power Array to get the UPS online.

If you were to switch out of Maintenance Bypass at this time, the UPS will remain in bypass as the Power Modules cannot start without adequate battery bus voltage, and therefore there is no conditioned power to supply to the load. Only utility is available thus the UPS stays in bypass until power modules can start upon the insertion of one good battery module (assuming all dead batteries have already been removed).

[Anonymous user]

Yes the PS fans are off. The batteries were replaced late 2008, so it's funny that they would be bad already. The unit has been in maintenance bypass for about 2 weeks.
Would it help if I removed the batteries one by one and re-inserted them or are they really dead?
Thanks for your help...

[BillP · Accepted solution]

It is unfortunate that the batteries were left in the UPS while it wasn't operational (maint bypass). APC warns against this practice in several ways, from putting warnings on new Symmetra chassis to Public Knowledge Base articles to warnings on the SYBATT modules themselves.

[KBase 1512 discusses this topic.|http://nam-en.apc.com/cgi-bin/nam_en.cfg/php/enduser/std_adp.php?p_faqid=1512]

I have attached an image of the warnings placed on the front of every SYBATT battery module.

All of those batteries have been destroyed and must be replaced. Do not attempt to forcefully recharge them as severe battery damage may result. This type of user error would not be covered under the SYBATT limited warranty.

Please feel free to contact APC Support at 800 800 4272 or us here on the forums if you need further assistance in bringing your Symmetra back on-line.

[Anonymous user]

Thanks JoeMomma for all your help. New batteries are on their way.