I have 2 AC300s, 2 B300 and 4 B300k, I have the fusion box for the mean time and the integration kit to install. I need more panels. But my question is when I plugged in the fusion box and made them split phase, I could not pv priority with both plugged into power for backup at a certain low percentage. The other question is can I grid backup pv priority successfully? I heard that if the grid power goes down, the fusion box quits. Is this true?
Hi @DragonbloggerSheilaB, The purpose of the fusion box is to cut off the circuit by blowing the fuse when the current exceeds the rated value.
When you mentioned that the PV priority mode did not operate as set, it is possible that grid charging was enabled because the SOC fell below the configured threshold.
Please provide a screenshot of your UPS settings, the set SOC value, the actual SOC at the time grid charging occurred, and the PV input power.
Hi @dwatrous, We appreciate you taking the time to test your AC180’s performance. For the most accurate capacity measurements, we recommend using a load of around 1000W during testing.
With smaller loads, the unit’s base power consumption (self-discharge) becomes a significant factor, skewing your results
Larger loads minimize this effect, giving you a truer measure of actual capacity.
The AC180 has different running times depending on the device you’re using it with.
For high-power devices, the running time = Battery capacity × DoD × η ÷ load power.
For low-power devices, the running time = Battery capacity × DoD × η ÷ (load power + self-consumption of AC180).
DoD refers to Depth of Discharge and η is local inverter efficiency.
For AC180, DoD is 90%, η is 85%, and self-consumption is about 15W.
E.g. If you run a 100W blender with it, the running time will be:
1152Wh × 90% × 85% ÷ (100W+15W) ≈ 7.66 hrs
Note:
- The formula is NOT suitable for inductive loads with compressors, like refrigerator, air conditioner, etc.
- The above data is for reference ONLY.
Thanks for the responses. My purpose in purchasing this was for an off grid septic system and pavilion. The primary constant draw against the battery will be a small air pump (assumed to be inductive) which draws about 35W. This will run continuously. Less frequently there will be additional draw for a water pump and some LED lights, etc.
I don’t suppose there’s anyway around the inefficiency you describe, so most of the time it seems I will be dealing with as much self-discharge as draw against the air pump. I just need enough capacity to make it between solar charging and for the battery to charge sufficiently during the solar cycle to reach full charge.
I am aware that I may need to add a second solar panel to reach full charge. It sounds like I might need to add a second battery also to have sufficient energy with self-discharge to keep my air pump running continuously.
What I want to do is to have a failsafe for if power dips below 20% in and pv set for priority ups as working mode and soc is actually at 30%. I don’t think it was charging at the wall. Just one I could plug in but not two, two would kick it off. Doesn’t really matter, I could unplug both if I want to run the clothes dryer. I will be integrating soon anyway.
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Hi @dwatrous, Thank you for the update. Yes, to maintain sufficient power, purchasing an additional solar panel will result in better charging performance.
Please note that the solar panel needs to be of the same model, and the total voltage after connection must not exceed 60V.
Hi @DragonbloggerSheilaB, Thank you for sharing. It seems you are a professional in this field.
Generally, our devices are set to prioritize PV by default. However, when the power level is too low, it is more reliable to switch to the grid on time.