If your battery´s are new, like less then 4 complete dis- en re- charge cycles. I advise you to put your battery´s through at least 4 complete cycles Discharge to auto shut off and recharge to 100% 4 times then do the test again…
Good to know. Will do. Thanks.
Hi @electricadventure, In my opinion, this is the normal condition.
When the machine is on, especially when the AC output is turned on, there is a self-consumption of power. This will consume some energy to maintain its operation.
@Selfmadestrom’s correct, we suggest you calibrate every 3 months.
I calibrated the AC200L with B230 attached by cycling four times to 100% and then to 0% when it shuts off.
I then repeated my test but gathered six data points during the discharge until only 3% on the AC200L and 2% on B230 were left after 18 hours 46 minutes elapsed. These data points were % remaining on AC200L and B230 as per Bluetti app, kWh consumed by the computer equipment as per Kill-A-Watt, and time elapsed in minutes as per Kill-A-Watt. This data showed that approximately 120W were used to operate the AC200L/B230 pair. In other words, over the almost 19 hour period, more than half of the 4096Wh of battery capacity was used by the AC200L/B230. The W used by the AC200L/B230 calculated from the data ranged from 113 to 125 W, perhaps due to slight inaccuracies of the % battery remaining.
Hi @electricadventure, We would like to confirm if the BMS version of your AC200L is up to date. If it isn’t, we recommend disconnecting the B230 and updating the BMS.
Additionally, when recalibrating the battery, could you try disconnecting the B230, and then discharging and charging both the AC200L and B230 separately?
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Have you checked if the Kill-a-watt has the correct power factor set in its settings? What was the reported AC output power on the AC200L’s screen when it was powering your equipment?
That seems like a lot to me too (Read the forum below and the table given by M.Briney).
In addition to recalibrating the two units AC200L and B230 to be done separately, you can also do the following test, with the B230 plugged into the AC200L, turn on AC without plugging any devices into the AC sockets and see after 3 to 4 hours how much you lost.
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The BMS version of my AC200L is up to date. I can do another calibration but I don’t believe that is an issue. The W used was pretty consistent with the % decline.
Hi @electricadventure, The issue seems to be related to the self-discharge of the AC200L. When the AC output is active, the AC200L consumes 18W per hour. If you want to monitor the load time of the AC200L, we recommend using a higher-power device so that the impact of self-discharge on the AC200L is negligible.
The best solution is to use solar panels in conjunction with the AC200L, as this provides a continuous and free source of energy, eliminating concerns about power loss.
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They were consistent.
I recognize there is consumption when it is idle with just the units turned on and AC turned on without a load. However, I was interested in the consumption with a load. I haven’t tested without a load. Perhaps the Wh used by the load could make a difference too.
I understand the time period makes a difference. However, the consumption with a load is substantially higher than without a load with just the unit on and AC on. I expected that a 4kWh battery would be able to run this equipment without solar for a longer period.
BTW, I have installed solar panels on my standing seam metal roof to be the main source of electricity for the AC200L and perhaps an AC500.
My reasoning is as follows:
1 - Either your ac200l and b230 have no problem, but simply the calibration is no longer good (for example when the Soc indicates 3% in fact you have much more energy than 3%): a recalibration of each unit separately should correct the problem.
2 - either your wattmeter/energy meter does not correctly measure the energy consumed… (It measures less than reality)…then a test without load (but with “ac” on) could allow you to better evaluate the self-consumption.
3- if after having done the recalibration in 1) and the test in 2), you still find a self-consumption of more than 100W… Maybe you have a hardware problem with your Bluetti.
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1 - I just recalibrated 4 times.
2- Watt meter isn’t an issue
3- The self consumption is far greater when there is a load on the AC than when there isn’t. This is clear. Is it a hardware issue with my AC200L? Maybe, but I’m inclined to think this isn’t unique. It makes sense to me that the W consumption would be greater with a load. I was quite surprised by how much it is though.
“Is it a hardware issue with my AC200L?”
To be honest, I don’t know.
If you are sure that your wattmeter is not a problem, then it can only be the ac200l.
But can I ask you how you can be sure that your wattmeter is not under-measuring the consumption of your appliances (fridge) ?
When you measured the consumption in idle (with ac “on” but no appliance connected… Did you find a figure of the order of magnitude of what Bluetti gave you? About 20W?
Correct. The power consumption of the AC200L itself is very modest with just the unit turn on with the AC switch also on but without a load. It’s with the load that the power consumption increases dramatically.
Hi @electricadventure, Please note that,
1/ The total capacity of the AC200L+B230 combination is 4096Wh. To protect the battery and avoid over-discharge, the battery is not drained 100%. The discharge formula is: capacity * DOD * n ÷ (load + self-consumption). DOD is calculated at 95%, and n is 93%.
The self-consumption when AC is on is 18W. Your load power is too low, so the effect of self-consumption is quite noticeable. We recommend using a load of 1000W-2000W to test.
2/ What is the ambient temperature where the machine is placed? Extremely high or low temperatures can have an impact.
3/ You mentioned that the self-consumption is higher with a load than without, and this is normal. When the load is applied, the internal temperature rises, causing the fan to activate, which naturally increases power consumption.
Thanks to @Snips1 for the helpful troubleshooting and insights, these have been very useful.
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Hi,
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I understand. I brought them down to 0% shutdown four times to calibrate and then once to measure the consumption with a load. I’m not surprised that a load of 1000-2000W would use dramatically less consumption of power by the AC200L, however, the use I was planning was to run a room of computer equipment with solar but the batteries ideally would hold enough Wh to run the equipment for at least a day or two without strong solar - that won’t be possible.
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Air conditioned room with temperature of about 75°.
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Yes, it makes sense. I needed to understand better the consumption of the AC200L for one particular use case of mine.
Thanks to all that have provided insights on this topic.
I have measured similar thing with AC200PL+B300.
So, ~5380 KW*h in total. x 95% x 93% = 4750.
Drained for 14.75 hours with median drain of 300W (fridge+PC), no more than 700. Ambient temp is ~25C.
12W is self-consumption, fan was working 1/3 of the time (but it should really be negligible, 10mm fan takes upto 1W). Let it be +1W for all this time.
so 4750 - 13 x 14.75 = 4560 - that should be ideal value it can give by specification.
However, external wattmeter showed 4820 was taken by my devices.
So, actually, real efficiency for me was ~90%, better than specification, which was pleasantly surprising.
P.S. It is brand new, 2nd full charge/discharge.
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