Symmetra PX 40k low runtime

[kfet]

Our Symmetra PX 40k had very low runtime, around 6 minutes. There are 16 battery modules installed. We replaced 4 of those battery modules with new battery modules. The runtime is still only showing 6 minutes. We performed an automatic calibration but it aborts after about 40 seconds and doesn't complete.

I also performed a self test then recorded the voltage during the test. Procedure found at https://www.youtube.com/embed/x-2gtqeCVZc

The voltage never went below 194.3. 

Is there another way to resolve the low runtime without having to perform a manual calibration? This will be difficult to do as we're only at 13% load and recommendations are to have at least 30%. We also don't want to bring services down.

Would it be a problem that we replaced only 4/16 modules? We wanted to make sure that replacing the modules resolves the issue before investing in replacing them all.

[KarimEissa · Accepted solution]

Hello,

First,if the batteries reached to 3 to 5 years service life,then it is recommended to consider replacing all the batteries at the same time as the weak batteries may affect the old ones and causes undesired runtime according to the connected loads

the RTC test places the UPS into battery operation. The test will only start if the battery capacity/fuel is 100%. The test runs until the capacity/fuel reaches 25%.

• An aborted calibration test can be caused by a mains failure during the test or if the low battery shutdown voltage is reached during the test period.
• Intelligence Modules running IM firmware version 20.0 and higher will adjust the displayed runtime based on the performance of the batteries during a calibration test.
• Resets of adjusted runtime values can be performed by serially logging on to the MIM and selecting the "Reset Calibration Factor" option.

The recalibration requirements are as follows:

 1) a >10% load must be applied to the UPS while on-line for several seconds prior to the discharge;

2) the capacity must be 100% prior to the discharge;

3) during the discharge the load must be stable (within 5%); and

4) the UPS must discharge to less than 35% capacity before returning to line (a complete discharge obviously meets this requirement and it's the most accurate method). If these requirements are met, the run time multiplier will adjust if it needs to (in either direction, up or down).

The NMC only shows the status of calibrations commanded by the NMC itself.

1) If you command the calibration from the NMC, then it will always say "passed" (even if a battery failed or there was a utility disturbance)

2) If you command the calibration from the Power View, then the NMC will show the status of the last calibration commanded from the NMC. If you have never commanded a calibration from the NMC, it will say "Failed"

 

Low Runtime observed on the PowerView display:

• If extremely low runtime (well below specification related to the connected load/batteries) is observed on the display (e.g. 1 minute) it is an indication that the runtime has been adjusted by the MIM. This indicates the IM firmware is at least revision 20.00>.
• MIM version 20.0 and later include an improved estimated runtime algorithm, which includes a runtime correcting factor
• This default value of this new parameter is 100, and it is re-calculated every time a runtime calibration is performed, or every time the batteries are discharged from 100% to 25%.
• If the batteries are new or have recently been replaced then the runtime calibration factor needs to be reset. This is done by logging into the MIM 

This will restore the runtime to the maximum value based on the number of batteries and the attached load. If it is suspected that the value was erroneously adjusted then the Calibration Factor needs to be reset and a new Runtime Calibration initiated.

updating MIM/RIM firmware or replacing it with the latest firmware 20.40 or higher  beside NMC updates to the latest version is recommended beside reset the runtime factor after replacing all the old batteries that reached its life time span can help to improve the runtime 

We recommends to contact your local CCC team to assist in SR intervention to update  the firmware of NMC beside MIM/RIM replacement to the latest version and ensure that all batteries are newly replaced and reset the runtime factor to resolve the runtime issues appeared in the unit 

Regards,

Karim

[kfet]

We checked the firmware version and it's v.20.10

How do we reset the runtime calibration factor? What are the commands?
Is it possible to perform those commands via cli over the network card, or do we need to console onto the MIM with the 9 pin cable?

[KarimEissa]

Hello,

This should be done using a special software tool used by our SRs to reset the runtime calibration factor by accessing  MIM/RIM serial ports ,it can not be done using CLI console access to the NMC

Regards,

Karim