Some of the UPS comments made in my prior recent postings before testing are corrected and clarified here.
I did some testing to learn about the different AC300 UPS modes and settings. Here are my findings, observations and understanding.
I do not have any solar or DC input connected to charge the AC300. I am only using Grid charging. So if there are any references of solar, it is only what the product panels or manual say or my understanding and not my experience or observation.
I did not observe any means to control when the AC300 would be able to stop powering the load by time of day. The Low SOC (State of charge) parameter, if available to be specified for that UPS mode, is the only parameter that can stop powering the load. When the battery state of charge depletes to the specified percentage, the inverter/AC output will be turned/cut off.
IE: setting the Low SOC at 20% directs the AC300 to turn off the AC inverter when the battery is depletes to 20% state of charge. As long as the AC inverter is on, (AC LOAD output switch) the load should be powered.
Other than option 1 Standard UPS, there are no references of the UPS directly powering the loads. Does that mean it only directly supplies power from the grid to AC loads through the AC mains in no other UPS options other than Option 1? And what does that really mean in regards to impact om the AC300?
1). Standard UPS – The AC300 will draw power from the grid to run the load and will use the grid to maintain the battery state of charge to 100%. The screen panel refers to the term offline UPS. Offline UPS to me means the AC300 is not actively running on UPS battery backup mode and the UPS function is monitoring the Grid power and UPS is offline in standby mode. When in this state, the AC300 UPS directly supplies power from the grid to AC loads from the AC mains. To me, that means Grid power is being passed through from the AC mains to the loads bypassing the use of the inverter when the grid is up. It will use the battery to generate AC power using the inverter when the grid is unavailable. When the grid is unavailable, the battery will continue to handle the load until it depletes its state of charge to zero and shuts down.
2). Time Control UPS – There are 6 time intervals that are available. There is a reset function to clear out the 6 time intervals to 0 time frames. You may set each interval to a parameter of charge or discharge. Charge to me means use grid charge. Discharge to me means no grid charge. Discharge does not mean use batteries to discharge to the loads. So the term is not that intuitive.
You can set Low SOC and High SOC parameters.
Low SOC (state of charge) means when the battery depletes to this SOC level, turn off the AC Output/inverter.
High SOC means the grid charges the battery to this level. Then the rest is reserved for solar/DC charging. If the battery SOC falls below this level, grid charging will start. If there is no solar/DC input, the grid charge will not be used to charge the battery’s SOC beyond this level.
Observation: The priority of the time interval parameters take precedence over the High SOC parameter. For example, if the High SOC is at a level requiring grid charging but you are in a time interval of Discharge, grid charging not allowed, the grid power will not be used to charge. If you are at a HIGH SOC level that does not require grid charging but you are in a time interval set for Charge, then the grid power will be used to charge the battery until it is 100% charged. If the current time does not fall in any specified time interval, then the High SOC will determine whether to grid charge or not.
3). PV Priority UPS - only a SOC percentage parameter is used. No time intervals used. The percentage to me is the same meaning as the High SOC. The grid is used to charge the battery to this percentage and the rest is reserved for solar/DC charging. To me, this mode is a little ambiguous. Plus I don’t have solar so not much I can report here.
4). Custom UPS – There are settings to enable or disable Grid charging and/or Time control grid/no grid charging. Similar to the #2 Time Control UPS, there are 6 Time intervals and Low and High SOC settings. To me, using this mode instead of using Time Control UPS offers a quick way to turn off grid charging and or time control grid charging without the need to change the parameters.