Hi, could someone please explain to me:
I used the power station for the first time today, and got really bad output:
EB70, fully charged, with 150kw as output, only lasts 3 hours then the battery switches off (drained).
Is this the norm for this machine (although output is listed as 1000kw)? Or am I doing something wrong?
Hello! I do have an EB70, the USA version. The numbers you are stating don’t match up to my device, but it might just be a matter of units of measure. For example, my EB70 can output 700 watts of AC power, and the battery is 716 Wh (watt-hours). In a perfect world without any losses or inefficiencies I could run a 700 watt device for an hour. But, the AC inverter uses power to convert to AC, so realistically I could expect about 90%, maybe less, of the battery capacity, so closer to 640 watt-hours. So a 700 watt device would last around 55 minutes, and a 400 watt device would last about 1.5 hours.
When you stated your output was 150 kilowatts, did you perhaps mean 150 watts? If that is the case, then it should have operated that device for about 4.3 hours. If you happened to also have the DC output turned on it would have drained the battery quicker than that. But I’m not sure what you mean by output listed as 1000kw.
Feel free to ask more questions and I’ll try to better understand the issue.
@Amelia When you receive the power station, please do a full cycle of charge and discharge at the first time.
Furthermore, 716Wh × DoD × η ÷ (load power) = running time (estimated)
Note: DoD refers to the Depth of Discharge, η is the local inverter efficiency. DoD=90%, η=90%. (Load power and charging time are measured in Watt and Hour.)
Hi Henry,
I am using the South African version of the device.
I am running my TV, Wi-Fi Router and DSTV decoder on the machine (AC).
Samsung TV = 180w
DSTV decoder = 50w
Fibre ONU = 5w
Wifi Router = 10w
It is set on Eco and 50hz.
The “output” is 155w (I have attached a photo of what I mean)
It only runs for 3hours, and then shuts down
I have done the discharge and recharge exercise twice.
Should it not be able to run for longer, as the output is not that high?
Can you maybe assist with the hour calculation?
@Amelia When you do the full cycle of charge and discharge, please ignore the SOC. Please completely drain the battery until it automatically shuts down, and then charge it with AC until it is fully charged and automatically shuts down. If this doesn’t work, the EB70 needs to be repaired. Waiting for your update.
Hi
I’d be very interested to know the outcome of this thread discussion. I’ve recently bought an EB70 and have used it to power a Waeco cooler while camping. This cooler is rated at 45W, but obviously the power it requires varies according whether the cooling fan switches on or off. This can be affected not only external temperatures, but also whether the coolbox is already cool inside.
I set up a test of this set up at home. I first powered the cooler of AC mains power overnight. Then the next morning, I put in 3 Yeti freezer blocks, 8 small bottles of beer that had been cooled and briefly put in the home freezer, and a few items of food from the fridge.
I connected the EB70 to the cooler and set the cooler to its 2nd lowest cooling setting (i.e. ‘Eco mode’). Observing the unit during that day, it often required no power from the EB70 (or at least, the output display on the EB70 read ‘0’). Other times it showed output between 10-20 watts. The EB70 battery was pretty much empty (low battery display showing) by around 24 hours.
If I multiply the max output display (20 watts) by time (24 hours), that only amounts to 480 watt hours, well below the 716 watt hours the EB70 is advertised at. I understand from other posts that there are inefficiencies inherent, and more so if AC output is used (which I did), but it still seems a disappointing return, given how cold the cooler was at start up and how much ice/frozen items it contained.
Appreciate anyone’s input here.
Thanks
Hi @Philby, Do you want to test the actual usable capacity of the EB70?
We recommend not using a cooling unit as the test device. Please note that for some machines with built-in compressors or condensers (such as fridges, air conditioning, pumps, and freezers), the surge power will be 3-7 times higher than the rated power, and it will keep several seconds after it is just turned on. Please consult the supplier of your device for more information.
At the same time, low temperatures can also affect battery performance.
Were you only turn on the AC output to power the cooling unit? When the AC output is on, the EB70’s self-consumption is 16.5W per hour, so please be mindful that this could impact the test results.
Generally, we suggest using a constant power load around 1000W to minimize various influences and obtain a more accurate result.
Running time = Battery capacity × DoD × η ÷ Device rated power DoD refers to Depth of Discharge and η is local inverter efficiency.
For EB70, both DoD and η are 90%. If you run a 500W blender with it, the running time will be:
716Wh × 90% × 90% ÷ 500W ≈ 1.2hrs
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 response.
I understand the point around using a cooler box as a test device (re power surge), though what I don’t understand is that there is an output wattage display on the Bluetti power station - surely, this displays output wattage, including output wattage as part of a surge?
I’ve also used a wattage meter, plugged into the AC outlet of the power station, which the cooler is plugged into. This records not only ongoing wattage output (which roughly matches the display on the power station), but also total wattage output over a period of time - and this shows only about 400 watts total for a complete power station drain.
I’ll also add here that because I’ve loaded up the cooler with freezer blocks and frozen beer - and set the cooler box to the lowest or 2nd lowest cool setting - that there are not many instances during the tests where the power has actually surged.
Also, you said that ‘when the AC output is on, EB70s self-consumption is 16.5W per hour’. Is this in addition to any devices taking charge? So, if the power station output wattage shows ‘10’, you have to add 16.5 to that figure for wattage output of 26.5W? First, that seems a lot. That is, over a 24-hour period, 396 watts (24 x 16.5) - more than half the power station capacity is used up because output is AC? If so, wow! Second, if this 16.5 watts does not get displayed on the power station’s wattage output display, then I’d say that the display is not that useful (or at worst, downright misleading!).
I don’t know what you mean by ‘low temperatures can also affect battery performance’ - I didn’t put the power station inside the cooling fridge! It was on the floor next to it - ambient temperature about mid 20s Celsius.
Appreciate your explanations so far - if you could confirm, clarify or explain any of the above points, I’d be grateful.
Thanks and regards
Philby
Hi @Philby, Yes, the EB70’s output power displayed includes surge power. The power variation of a cooler box, compared to a constant load, can be quite large. For example, when the refrigerator door is opened or when there are internal temperature fluctuations, it can significantly affect the test results.
Self-consumption power is not displayed in the output power because it is used internally rather than being output. However, it will reflect in the final test results. Every electrical device consumes self-consumption power to maintain its operation, and this is a reality that cannot be avoided. To minimize the impact of self-consumption power, you can turn off AC/DC output, which can reduce the effect as much as possible.
Regarding the environment temperature of 20°C, we believe this is very suitable and should not affect the test results.