SMT1500....battery drain when switching to green mode?

BillP · ‎2021-06-28

This problem started in the last week or so. I did have a long power outage before this happened if this helps. I have this unit attached to my home PC. Anyways, after some research and going through event logs, this problem only occurs when green mode starts. When my UPS is at basically 0% load when my PC is off, or avg. around 30% on, problem is the same. What happens is about every hour, I'll here the "click", and going by logfiles, my UPS enters Green Mode. At this point I'm at 100% charge. After the click, over about a 5-10 minute period, my battery will drain to 95%(always same). At this point, another "click" is heard, and Green Mode is exited. Next, my battery will charge back to 100%. Another hour or so passed, and this starts all over again.

A few other points. Input voltage is about 115v when occuring, so no problem there. My unit itself is about 5.5 years old. I replaced the battery in Dec 2014 w/ new correct OEM APC battery. I tried both a self-test and battery rundown calibration yesterday, but they had no affect. Same problem. Again, I'm sure its tied to green mode. When this problem happens, I'm NOT switching to battery. Green light is always lit on front of UPS, no fan switch to high, beeps, ect. I've read that Green Mode cuts power(unless needed) to AVR circuitry to save energy. I'm thinking that when this happens, perhaps due to age, the transformers start drawing power from the battery. Maybe there is a failsafe of some sort in the firmware that senses a problem because every time at 95%, Green mode disengages, and battery charges back to full.

I'm hoping someone here can help. I should mention that outside of hearing the "click" and physically watching the drain, my UPS seems to run fine. I just happened to notice this by chance a few days ago. Also, I don't see an option in either the front panel advanced menu settings or in Powerchute Business software to disable green mode all together. Thanks for your patience in reading this.