I have a portable PV380 and PV420 that I hook up in series when I am boon-docking. They seem to be working well and they do get me back to 100% however I could use another to recover faster. Both have been discontinued and my hunt for used ones has been unsuccessful so far.
Does someone have a suggestion for an additional portable panel setup that would work with these two?
Specs on what I have for reference:
PV420:
Voltage at Max. Power (Vmp): 36.6 V
Current at Max. Power (Imp): 11.5 A
Open Circuit Voltage (Voc): 44.3 V
Short Circuit Current (Isc): 12.2 A
PV380:
Voltage at Max. Power (Vmp): 37.9V
Current at Max Power (imp): 10A
Open circuit voltage (Voc): 45.5 V
Short circuit current (Isc): 11.3A
To answer your question, you need to set some limits.
What are you charging with these panels?
Max Volts and Amps input are the limits referred.
Re your current panels - In Series you add the Voc = 44.3+45.5 = 89.8 as the input limit so far.
Re actual output - Add the Vmp = 36.6+37.9 = 74.5, then multiply by the lower of the 2 Imp values 74.5x10=745W. This is the theoretical maximum from your total array of 380+420=800W.
To recommend an additional panel, you need to answer Q1.
Thank you for responding. The use is for my RV. I have a solar controller for the roof panels and a separate controller for this ground deploy setup. I would like to add another 300 to 400 watts to my current ground deploy I listed above. I am not sure if the 350 watt portable set up currently offered by Bluetti would drag down the ground deploy panels I am currently using. With the current array I am typically seeing about 520 watts in hot weather. I would love to find another PV380 or 420 to make things simple.
Ok, that is part help, lol. From this I assume you have RV house batteries and the extra panels will work from an existing Controller?
You need to look for a panel that is nominally 24V as that is what the Voc indicates.
Providing you look for a panel that has a nominal 400W give or take 20-30W and it’s Voc is no lower than the 36.6V panel with a similar Imp, you won’t drag them down if you connect 3 panels in Series to the same controller if its Voc limit will accept around 110-115V.
The other option is to get a further controller and what ever panel or panels suit and create a 3rd string of Solar, it should not interfere with your existing setup, particularly if you are using LFP batteries and they can take that amount of charge. You will need another input connection for this.
I actually have 3 inputs to my caravan;
Is an on Roof 160W into the primary battery management hub. (Solo connected)
Are 2 x 150W ground Mats with stands through a Victron Solar Controller. (In Series as the Victron will take that Voc
The 3rd string is 2 x 120W solar blankets into the solar input of a Redarc DC-DC, which is the charger powered by the 4x4. (In parallel as the Redarc Voc limit it too low for Series.)
Their negative lines all go through the fitted Shunt, so input is recorded via the primary BMS display.
I have LFP batteries and they take whatever of the above I throw at them.
(points 2 & 3 are extra Anderson plugs I wired from outside to the controllers)
Thanks for sharing your setup that helps a lot.
From what you described, you’re already getting around ~520W in hot conditions, which is actually pretty solid for a ground deploy system. Adding another 300–400W should definitely give you a noticeable boost, especially in less-than-ideal sun.
About the 350W portable panel from BLUETTI — it won’t exactly “drag down” your existing panels as long as you’re not mixing them on the same controller input. Since you mentioned you’re running a separate controller for your ground deploy, that’s actually the best-case scenario. Each array can operate independently, so mismatched panels won’t interfere with each other.Where issues usually happen is when different wattage/voltage panels are wired together on the same MPPT input then the system tends to operate at the lowest common performance point.
If you can find another PV380 or PV420, that would definitely be the cleanest solution. The Bluetti PV420 solar panel for example runs around 420W with similar voltage/current characteristics and up to ~23.4% efficiency, so matching panels keeps things simple and efficient.
If not, adding a 350W panel on its own controller is still a perfectly fine workaround you just won’t get that “perfect matching” efficiency across one array.
Honestly your current numbers already look good for RV use. With another 300–400W, you should be in a really comfortable spot for most off-grid situations.
If you want, tell me your controller specs (voltage/amp limits), and I can double-check the best panel combo for your exact setup.
