A lot of good info there, thanks for that. Without delving too deeply into power supply design theory and battery technology, a great first step for anyone is to just kill the power either locally (that one receptacle or that room) or (preferably) globally (the main breaker for the whole house... just to answer the most basic requirement: The Function1 test, to wit: Does the system STAY RUNNING when the power is killed out?
We can explore how long as another exercise, but first... it has to stay ON as step one.
I have three separate UPSes in three locations (at the PC and also three switches in two different locations) and if I had simply flipped the breaker to test function1 after the last time I messed with rearranging the closet, I could've quickly resolved that my recent movement of things had left two switches plugged into the "surge-only" outlets of the switch closet UPS.
Dumb. Simply careless to not test after the work, but it would be better to routinely test on a schedule.
True a functional test is absolutely required but lets expand on this for the benefit of others. As you correctly noted you can simply unplug the UPS from the outlet or at a intermediate / global level and turn off the breaker(s) / main principle. The obvious first thing you or anyone wants to see first is the attached load is running. Next, the UPS alerts you via audio notification and if the UPS is so equipped sends an email to affirm the same.
The next important thing is (IF) the UPS is tasked and connected to a computer system like BI. That the system will invoke the graceful shut down sequence not only to extend the runtime but also to protect the operating system from file corruption.
If we assume for just a moment the UPS isn't attached (communication link) to a computer system. We want to see first hand how the runtime minutes vs the actual operational runtime compare. You'll quickly find out that the display (run time) doesn't match how long the system actually operated for. You may also find out the time on the UPS begins to zip down quickly vs what was seen in the past.
To over generalize this tells a person several things and if we just assume the UPS is brand new and the cells inside the unit are fresh and 100%. We also assume the connected load is within the makers rating for X minutes per so many watts load.
Whether that be 5 minutes at 100% load say 500 watts. Maybe 10 minutes at half load (250 watts) etc. If the UPS offers that run time during the live validation tests this tells you when the UPS is brand spanking new it was designed correctly and the paper metrics do reflect the real world use!
Now, if you performed the exact same test and everything was exactly the same (test parameters) that simply affirms the UPS isn't well designed or overly exaggerated.
If a person changes only one parameter like higher load than rated you have just exceeded the capability of the UPS.
So, connect the proper amount of load to the UPS to obtain the rated operational runtime.
Now none of that applies after the first year if the unit was called to duty just once never mind 2-30-99 times!
This is why monthly, quarterly, and annual validation tests must be done to confirm the UPS is fully operational. On a completely separate track one of the most important tests a person can ever do is validate how the UPS will behave once the battery is fully depleted (empty) and than when 120 VAC POCO power is restored.
You'll quickly find out some UPS systems will absolutely not turn back on. Some will come back on but will NOT provided any UPS power to the loads until such time as the battery is fully charged. Everyone must test and validate the UPS in place does or doesn't operate like this.
Some may call this a design flaw while others say this is a feature!
Only the person and environment can say what behavior is correct / wrong. It should be noted more advanced and expansive UPS systems have the very same power options which should be reviewed and enabled / disabled per your own use case and environment. Since this is a video security system we don't want the UPS to remain off. We either want it to be programmed for
Last known state or
On upon power restore.
Generally speaking (I'm going to over generalize) the phrase fail safe vs fail secure. Each method serves a purpose to a person and environment. One only needs to think about a few things in the home where we absolutely want said item to receive power upon restore of 120 VAC.
Think: Fridge, Freezer, Sump, HVAC, etc.
Other things to keep in mind is when a functional test & validation is being done. Its imperative you have some kind of tool to measure inrush current. Because you will quickly find out say when a person has a old school monitor connected with the system it will literally cause the UPS to fault out.
Why???
Because regardless of the power rating the UPS maker should / must design their systems to offer enough power when heavy loads are attached. A small toaster sized UPS is going to either fault out and not turn back on or struggle when a connected device like a Enterprise POE Switch which spools up with Mach 2 fans for the first 30~ 120 seconds kicks off!
More advanced and expansive UPS systems offer timed (load) outlet activation along with load shedding. Having these features is incredibly useful when your system is large or complex. Other important functional tests are to visually and auditorily confirm if the UPS has a fan that it does operate (IF) and only if required. Many cheaper UPS the fan always runs or turns on only when the UPS is on battery. Other more advanced units manage the fan based on the load and heat generated via PWM or simply cycle it on and off based on a defined threshold.
If your UPS has a fan just like any computer system use the monthly / quarterly test to inspect and clean the area. Other important considerations is to touch and listen next to the UPS. If you don't know your specific unit makes a buzz / hum how will you ever know if that's normal?? Conversely, if you begin to hear a buzz / hum when such a noise was never present its imperative that you inspect the battery for swelling, bulging, or blown vent caps.
Almost every UPS system on the market today has some kind of thermal sensor to detect an over heat condition.
Don't ever rely on this safety mechanism to protect you or your home!
This leads to fire mitigation and best practices as it relates to anything that can store massive amount of energy. Always have a properly rated ABC fire extinguisher near by in case there's an electrical fire. More advanced and expansive UPS systems have what is called a EPO.
The Emergency Power Off is simply a contact that allows a person to connect to a kill switch. Should there ever be a fault that needs to be addressed pressing the EPO button will immediately turn off all connected loads but will turn off the UPS.
The EPO switch does NOT remove the electrical power from the battery cells . . . So great care and handling is still required should a battery fire exists. This leads to basic safety and storage of said UPS system no matter the type or size.
Do not leave any UPS on the floor . . .
It doesn't matter if its designed to be sitting on the floor . . . The UPS should be sitting on / in a fire / chemical resistant mat or enclosure.
