AC180 dc charge limited to 100w

My new AC180 seems limited to 100w dc charge even when plugging in my new MP200 solar panel.

Sunny day and about 21 degrees C. O/C V = 20.9v , S/C current = 9.1 a (appx 190w)

But input watts never gets above 115. I have connected a fixed 110w panel to the AC180 and I get around 100w input.

Is there a wattage limit on the dc input side? Or am I missing something?

Sorry for the reply to my own post, but I have further information.

AC180 is reporting 15.1v in the PV Information on the Bluetti App. But I measure 20.9 across the input plug.

That manual shows 500W/10A max. Voltage range is 12-60VDC.
Are you using a long and/or thin cable?
I’ve only used at least two panels in series (~44V) with mine, so I’m not sure how it behaves with lower voltages. If the suns out tomorrow, I’ll try a single panel to see how it does.

Thanks. I am just using the supplied cables that came with the AC180 and the MP200 solar panel. In full sun I was getting 20.9 volts @ 9.1 amps at the plug (I realise o/c voltage and s/c current is not an exact measure), but the AC180 was reporting 15.1v @ 7.9v (120w). My concern is that I will not get much better sun conditions than this and If I am getting 120w max then the MP200 is pretty much useless to me as my fixed panel on our caravan is giving me just a little less and it is rated at 100w.

@BBB AC180 will not limit the DC input to 100W. The max limited input is 500W. It seems that the voltage of the MP200 is too low. You can try other solar panels to test.

I did a few tests with my AC180 and a single 200W panel.
Panel specs: VOC:21.8, Vmp:18.6, Imp:10.76, Isc:11.47.
It’s an “Ok” panel that was on sale.
Sun is out, but it’s a bit hazy and of course not the best time of year.
The app showed 127W, 15.9V & 7.9A
My solar panel meter, going through the same cable, showed 143.5W, 14.66V, 9.79A

You will always get higher voltage from the panel before it is connected to a load. After the load is connected you are seeing the lower voltage. Unless you get your voltage up in the 20+ volt range you are not going to get very good performance.

Thanks, yes I understand the specs. If you see my original post you will see I have tried another panel which is rated at 100w and gives only slightly less input power.

The MP200 is sold as a package with the AC180 (which is how I purchased it) if the MP200 only gives a marginal improvement over a 100w panel, it does seem a little misleading to sell it as a package.

The AC180 IS current limited to 8 amps until the input gets to 32v as seen in this video (18 minutes)

That means that the MP200 can only ever deliver around 170w.

Thanks, yes I understand that measuring o/c voltage is not an ideal gauge, but this panel is sold as a package with the AC180, I am using the supplied cables and am in ideal solar conditions, how would you propose that I get the voltage higher?

Thanks for doing this testing :slightly_smiling_face:. Your results are similar to mine and also confirm the 8A limitation as described in the youtube video I attached in an earlier post.

I tested my AC180 on solar with a moderate sunny day. I have 2 x 150W Hardkorr solar matts and have made up 2 cables with Anerson plugs both ends as I use them for other charging. Both cables are 1 plug into 2 plugs, (doubler) one wired in parallel and the other in series, then another cable, Anderson to MC4 to fit the AC180 cable.

If I connect in parallel the solar output is approx 20V and 17A, which is over the 10A limit, which defeats the purpose of having the 12-60V limit at 10A. So my test was with the series cable which gave me 240W input on the AC180. The approx panels in series output was approx 38V and almost 6.5A, neither of which is max output of the panels. I put that down to sun conditions.

The trick with solar input is to use 2 nominal 12V @ upto 300W each to get near to 500W, or a 24V nominal panel as they have an open circuit V approx 45V.

As an aside - I am not happy with the limits of car charging as most users, including me, get around 80-90W from the cigarette plug. As I have an auxiliary battery in the 4x4, I’ve wired an Anderson with a 50A fuse to it, to plug into a 375W Victron Pheonix inverter. When the AC180 is set to charge from mains/grid in Silent mode it draws 280W, which is well within the limits of the Pheonix. When driving I connect the AC180 to the inverter to charge 3 1/2 times faster than the 12VDC cig plug. I’ve tested this setup and it works very well, which is particularly of use in winter when solar is very poor.

The aux battery has DC-DC charging and an upcoming 4x4 solar on roof panel another 5A. The test I did with engine idling showed a net -18W on the auxiliary battery without the solar panel, very manageable.

Yea the low DC/Car charging limit is set the way it is because 99% of people just would be using their factory 12v cigarette plug and those are no way setup to provide more then 8-10amps. Have heard FAR too many stories of people popping fuses and/or melting wires and the last thing people want to deal with is potentially frying some electrical components inside their vehicles. haha So I totally dig your thoughts in going with the victron setup man! Sounds like you got it dialed in pretty solid for your specific use-case and your vehicle. I still need to do the same with my subaru outback, as the little 12v plug in the trunk space is very convenient for powering a cooler or whatever, but it definitely isn’t ideal for charging anything at the same time when in between road-trip destinations. Cheers and thanks for sharing!

Here’s a wiring diag of my 4x4 setup. It’s on my CAD system so I’ve annotated it and posted as a .JPG screenshot.
I’ll explain a couple of things in next post, might help you figure out what suits you. :slight_smile:

If you save the .JPG you can zoom for better detail. I have a false floor in the rear of the 4x4 (AU) driver’s side has a single drawer and passenger side an Engel fridge freezer. The drawer and fridge slide are XTM brand. The neatest battery fit was a Baintech slimline and at the time I could only get a 75Ah with inbuilt DC-DC. The car in pos goes to the blue Anderson battery in, the neg to the shunt (Victron smart shunt), however there is a blank neg pin in the Anderson to battery for better location. The pos busbar is from Jaycar as it has a clear insulated cover and it allows for 2 output circuits for my use, but can supply 4. The main fuses are Midi due to load and the individual outlets are blade fuses of the correct amps for each device. More…

Not shown on the WD is my UHF, it is fixed to the inboard rear of the drawer and is powered by the 75Ah. I use a stubby antenna on the roof bar (approx 14cm long) and have run a Mic ext to the driver area of the 4x4.

I’m in the process of fitting a 110W solar panel on the roof and the output fuse area works as IN/OUT through the shunt. (Not shown)

I used the lids of 2 jiffy boxes to fix all the output Andersons, its input and the fuse block. This allowed me to hide all the wires underneath. The Shunt, pos busbar and both midi fuse holders are fixed to the false floor and as the whole system is Anderson connected, it’s plug n play. So far I have not drilled a hole in the 4x4 to fit everything.

I don’t carry the inverter all of the time, but will fit to the top of the XTM drawer as needs be. I t has a short H/D lead with Anderson to plug into the Aux battery lead. A small 240VAC ext lead from it to the AC180 pwr cable will charge from 4x4 when driving. The AC180 will travel in the 2nd row passenger side footwell.

Hope all that gives you some ideas for your needs, lol. Happy New Year.

Oops forgot to mention, I hate cig plugs. They pop out when driving on rough terrain, don’t handle elec loads well and get hot. I use Anderson on everything as pos location and up to 50A.

However, I have a small jiffy box with Anderson input and 3 x cig sockets I can plug in as I have 2 spare outlets.

Does anyone have any ideas as to why the DC input side would be current limited to 8a unless the voltage is above 32v?

The 8A limit is primarily with car cig socket ratings. I have seen in the past that when close to max fuses blow. Which is why I rarely use them for anything other than a GPS, which is well below the rated max. The Hema Navigator is a 1500mAh battery and takes 4 hours to charge, without losses that’s 375mAh charge from 12V, so less than 1/2 amp.

With the lack of technical data, wiring or circuit diagrams provided to Bluetti customers, I would suggest this is a question for Bluetti Support.

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Just an update to my original post.

There was actually a problem with the MP200 panel that I bought as a package with the AC180.

The panel was actually only working as a 100w panel and not 200w.

Bluetti have replaced the MP200 and the new one is working perfectly (was getting 162W charge on a clear sunny afternoon), considering the 8 amp limitation this is much closer to expectations.

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Good to hear the issue is resolved and you are ready to go. Thank you very much for the update and resolution. Updates are key to understanding the overall issues with helping the group. It is usually a simple solution that is at the root of the problem but getting there can be frustrating at times.