Top Five: Undocumented AC500 Fixes/Improvements

Within the last couple of weeks, I received the long awaited P150D to P090D battery cable that allows you to attach a legacy B300 batteries onto your AC500. With this cable now in my hands I was able to migrate my home off my dual AC300 Split-Phase head-units and start some full scale AC500 testing!

Now as many of you have come to know, I have had my dual AC300 Split-Phase environment for nearly 9 months 24/7 and it's been providing over 650KW of power to nearly 70% of my home every month. So, you could say I was pretty happy... from that perspective.

However, the AC300 power station was far from perfect. Now, due to the size of my AC300 system and the through-put I was pushing through my system I was able to identify several issues and worked with Bluetti Engineers to both document these issues, but also work with them to test updates to resolve some of these problems.

For one of these issues, Split-Phase charging, I had to come up with my own "work-around" solution, because my AC300 power station was unable to service my loads while connected to the grid for charging in Split-Phase mode.

All of these things you can say frustrated me, but I saw the potential and benefits of the Bluetti power station, and I stuck through it... and I'm glad I did!

An Actual Owner, not just a YouTube Reviewer....

So being an actual owner, who uses my environment daily 24/7 to run my home, I'm able to see and experience things that a general YouTube reviewer does not and can't see....

And with that said, here are my top 5 improvements I saw in my first two week of using my dual AC500 system in Split-Phase mode....

1) Fast Running Clocks

This may sound trivial, but clocks previously running on the AC300 may gain an extra 1-2 mins daily.

Not the end of the world problem, but when you have trained your brain to look at a clock for the last 15 years or rely on a grid-powered clock as an alarm clock it can quickly become an inconvenience to have inaccurate time displaying on your clocks.

So why does this happen? Well, some grid powered clocks utilized the electrical grid power to count time (i.e., 60 hertz). This means that if the power running your clocks is off then your clocks time will be off as well.

Initially this was not something that my family or I was looking to be resolved when the AC500 took over... we got into the habit with the AC300 of resetting the clocks back to the "correct time" every week... but we noticed after a few days that with the AC500 the clocks were 100% accurate and keeping time properly. Over the next 2 weeks we're happy to say that all alarm and microwave clocks are still perfectly in sync.

2) Increased Voltage Output

On the AC300 the output voltage to your loads is 120 volts, which is to be expected. However, under medium load the AC300 can drop to 115 volts very quickly. Which isn't necessarily a problem, but with that type of drop you can quickly start to put your sensitive electronics at long term exposure risks. For example, I have several CyberPower UPS that protect sensitive electronics (computers, routers, security system) and would begin to reject the AC300 power during this type of voltage drop. In order to compensate this issue, I installed a voltage booster inline between my AC300 output and my loads that increased my voltage by 2% normally and by 10% under high loads. However, with the introduction of the AC500 system. I was very surprised to see the output of the AC500 to be 123 volts, which more closely matched the grid voltage to my house. I was even more surprised to see that under medium loads the system would barely drop to 119 volts and under high loads would maintain 117 volts. These voltage ranges where not only a lot better, but also were accepted by my CyberPower UPS units, which are designed to reject low or high voltages.

3) Strobing and Dimming Lights

So, this item is very closely related to my #2 item in my list. However, with the AC300 I was accustomed to lights in my home dimming when the furnace or microwave kicked on. I also learned that the light in my house would turn into a disco (strobe) when the washing machine was running... things you learn to accept when running on alternative power sources. I even had to purchase special LED light bulbs to reduce or eliminate the lightning issues. However, with the AC500 I was again happily surprised and very taken back when large appliances in my house were kicking on or actively running and I wasn't seeing any flickering or dimming, like I did with the AC300. Again, not the end of the world to have lights dimming... but this just shows you how much more powerful the AC500 inverter is and how much more stable it is! This is impressive because even with most gas generators you will see light dimming or flickering.... no longer with the AC500.

4) Split-Phase Charging

This has to be my number one issue and frustration with the AC300. The ability to charge your dual AC300 Split-Phase environment from the grid (as backup) worked with great limitations. By limitations I mean if you run medium to large loads on your dual AC300 in Split-Phase mode the system would "trip", shutdown, reset and come back online. However, remove the grid power and the exact same medium to large loads would work perfectly fine on the AC300 in split-phase mode... very frustrating. Due to this, I ended up designing a "work-around" solution using T500's to charge your batteries off the grid, but this was an unnecessary step in my opinion.

In addition to the above problem, many users with the AC300 fried their systems during grid charging caused by an "alternative path to source" problem that the first edition AC300 had with non-neutral splitting transfer switches...

Therefore, I was very reluctant to plug my AC500 into the grid for direct head-unit charging.... but I'm so glad that I took the leap of faith... and I'm very happy to report that the Split-Phase charging is working 99% as expected.... why only 99%?... read #5.

5) UPS "Modes" that actually work.... in Split-Phase.

Ok, so I have to start off by saying that I didn't quote UPS for a reason... UPS stands for "Uninterruptible power supply", which in Split-Phase mode is not available for the AC300 and is still not available in the AC500. To explain, a AC500 in Split-Phase mode will maintain power to your loads when grid power is lost, this part of the UPS works. However, when grid power is restored, your AC500 in Split-Phase mode will temporarily cut power to your loads for about 1-2 seconds to sync-up with the incoming grid and then will restore power to your loads. Due to this failure to maintain power to your loads causes the AC500, and in fact the AC300, to not qualify as a UPS in Split-Phase mode.

Note: The UPS mode on a single AC300 or AC500 in single mode works completely. However, the AC500, much to the credit of the #4 item in the list, is now capable of balancing the grid, solar and battery power in Split-Phase mode as it was originally intended to do... Something that the AC300 simply couldn't do while in Split-Phase mode. This is also because the AC300 in Split-Phase mode couldn't fully accept grid power with-out failing.

So far I've been very impressed with how well the AC500 uses the grid for surge loads, when needed.... but sticks to the rules of the UPS Mode selected.

Initial Conclusion

So, we can see by the manual and the online reviews that the AC500 has larger specifications than the AC300 and should be able to service more loads.... but the five items above are undocumented surprises over the AC300...

Now I will have to say the AC500 is a step above the AC300, but it does have a few problems that need to be worked out. Here are a few items I think Bluetti needs to work on:

• The UPS should work in split-phase mode... I'm not sure if it's a hardware or software issue that can be corrected with firmware updates.
  

• UPS Modes need to be closely reviewed by Bluetti.

  • For example, PV Priority is affected by SOC Low and "SOC High" settings. However, SOC High is not an option to configure when in PV Priority mode. Time Settings may also affect the PV Priority mode as well.
    

• Manual is subpar, almost to the point of being unacceptable.

  • This not only leads to misunderstanding by the consumer, but leaves the door open for local city and counties to define their own rules on how a power station can be used with a building/home.

  • This also causes Bluetti support to be bogged down with unnecessary support questions that should have been answered in the manual.

  • Lack of Error Code Definitions. I'm not sure why the error code section of the AC500 was left out of the manual, but new owners are left reviewing previous models to get a list of error codes.
    

• Default error handling

  • This is basic computer programming... attempt to handle known errors, but when something unknown happens log this information for analysis. Both my AC300 and AC500 have randomly shut down and rebooted. It's a small inconvenience for a few seconds, but there is no error records or warnings shown on the screen.

If you're struggling in choosing between the AC300 and AC500, go with the AC500. Even if you don't need the power today that the AC500 offers, the benefits outweigh the slight savings.