UPS Won't Turn On

[global]

I went away for 4 days and powered down all the UPS's in my home office. when I returned, the BR1500MS wouldn't turn on. I went thru the trouble shooting charts and can only assume that the battery is kaput since it has a Quality Assurance Test Revision of 11/4/2019, and according to the manual the battery has a life span of only 3 to 4 years. I just want to get assurances from the community and support that my assumption is right since I tried every thing in the manual. What I find annoying, if it is the battery, I didn't receive any indication that it was going bad?

[Teken]

Take the battery out and measure the voltage and mark it down. Let the RBC remain disconnected and left on the table for 72 hours and measure again and report back the voltage.

A fully (100%) charged and healthy individual cell will measure 12.8 ~ 12.9 VDC relative to ambient temperature.

12 VDC is below 50% SOC (State of Charge) relative to ambient temperatures. A healthy battery cell will drop no more than 0.1 ~ 0.3 VDC after 72 hours. A drop in 1 ~ 3 volts after the initial surface charge has been removed indicates a degraded and EOL cell.

Your system takes a RBC163 which is two 12 volt 9.4 AH cells tied in series for 24 volts. You can buy the OEM RBC or rebuild the pack and reuse the connectors from the original to save finances:

https://www.se.com/us/en/product/APCRBC163/apc-replacement-battery-cartridge-for-backups-12v-9-4ah-l...

If you decide to rebuild the pack only buy high quality and (HR) high rate cells like the APC branded cells which are made by CSB.

Self Test / Battery Indicator: As you have already learned you can not rely on or trust these two methods to alert you of a unhealthy RBC.

The RBC is rated to provide 2-5 years of service based on usage, temperature, and environmental conditions. It’s designed to sustain 260 full cycles before signs of degradation subject to the same caveats listed up above.

Assuming you had absolutely no tools available the options are to replace the RBC every 2-3 years based on the power quality at the site.

Interim validation is to perform an annual lights out / grid down event test. By simply removing AC Mains and tracking how long the system continues to operate for and compare it to the APC Runtime Calculator.

Keeping in mind the online calculator is based on a new RBC using a defined wattage (load) at a specific ambient temperature.

If you mimic the same load and temperature and the following results are found:

Turns off immediately = Replace RBC

50% Runtime vs New: Replace RBC

75% or greater: Schedule RBC Replacement within 30-90 days.

Questions Ask . . . 👍

[global]

To measure the voltage, do I need a voltage meter? When I opened up the BR1500MS and pulled out the battery unit (this is before I initially posted) I unplugged the battery unit and when I plugged it back in, there was a small red light that turned on and off at the connector. I wasn't sure what I was doing at the time nor what the problem was since the BR1500MS had been operating without any issues up until this incident.

I've given this some thought over the past few days, I started thinking about the battery back up in the BR1500MS is intended to backup the BR1500MS when there is a power outage to keep the equipment operating that are attached to it? If the battery dies, the BR1500MS should still turn on and function less the battery backup? However, if the battery backup is integrated into the overall operation of the BR1500MS and interferes with it's operation while it is plugged into an electrical outlet, then of course it will cease to operate. Is this a correct assumption?

[global]

Do I need a voltage meter to measure the voltage, if so, I don't have or own one? Before I sent the original post, I opened up the BR1500MS, pulled the battery out and disconnected the left cable, I didn't know what I was doing so I reconnected the cable and noticed a small red light come on and then off. I don't know what that indicated if the battery is depleted?

Over the past couple of days, I started thinking the functionality of the UPS unit. My initial understanding is that the battery backup is intended to keep the BR1500MS operational and the devices it is supporting if there is a power outage. If the battery dies, the BR1500MS should still plug into an electrical outlet and keep functioning less the battery backup as it presumably did until I turned it off and then attempted to turn it back on 3 days later? The exception to this rule is if the battery is an integral part of keeping the BR1500MS operational 100% of the time? What would your reply be to this assumption?

[Teken]

You can purchase any quality multi meter from a hardware store or Amazon.

Ideally you would invest enough finances for a quality brand such as Fluke as this is a valuable tool for the long run and will serve you when the need arises for any DIY / Home User electrical diagnostics.

The cheapest Fluke Multimeter is the 101:

https://a.co/d/gAatLVv

There are many other quality brands such as Amprobe, Brymen, Greenlee, etc. 

You may also consider just borrowing one from someone for a few days. Given this may very well be a one time affair / need.

The specific model APC UPS you have has two rows of protected / unprotected outlets as seen on page 4 item 6. Which are unprotected outlets with no battery backup.

As such they should continue to operate and provide electrical power when the unit is on / off while connected to AC Mains.

Loads connected to the protected (Battery) only outlets would not work or provide any electricity if the battery was dead or the system was powered off.

Your system takes a APC RBC163 which you can purchase directly from APC / Reseller:

https://www.se.com/us/en/product/APCRBC163/apc-replacement-battery-cartridge-for-backups-12v-9-4ah-l...

To save finances you can also purchase the raw cells and rebuild the pack by reusing the connectors on the cartridge.

Going this route will easily save you 30% or more if that is important to you. 

https://download.schneider-electric.com/files?p_enDocType=User+guide&p_File_Name=BU+UM+990-91003A+MN...

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