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How much can I over panel my 250/100 Victron Controller?

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brandonboosted

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I don't want to add another controller and combiner box at the moment but would like to utilize the most of my panels in these winter months. Can I over panel my 100A Victron controller by 50%. Panels are 320W 10A. Panel Configuration would be 5S x 3P =150A (200V). Any help is appreciated, thanks.
 
That doesn't even seem like overpaneling (assuming that's a 48V charge controller)
 
That would be 30 amp, not 150 amp.
And 160 volt.
brandonboosted said:
I don't want to add another controller and combiner box at the moment but would like to utilize the most of my panels in these winter months. Can I over panel my 100A Victron controller by 50%. Panels are 320W 10A. Panel Configuration would be 5S x 3P =150A (200V). Any help is appreciated, thanks.
Click to expand...
 
5S3P is 15 panels. 15 x 320W = 4800W. At 24V that is 200A of charge current. That's double what the 250/100 is meant for. That seems to be too much.

You might get away with it if you aim the 3 strings in three different directions such that you never produce much more that about 2400W at any given time.
 
timselectric said:
320w 10 amp panel, should be about 32 volt.
5s would be 160 volt.
Click to expand...
Vmpp would be about 32V. Voc is more like 40V. I have 330W panels and the Voc is 40V.

Either way, 5S is well under 250V even in -40º temperatures.

The issue is the 200A charge current from 15 320W panels.
 
Data point:

I have a 5s3p @305 watt panels aimed south on a single 250/100 for the past 3 years, not an issue yet, 48v.

I believe the 250/100s limit is 70amp input and will self regulate on the output.
 
dr.diesel said:
I have a 5s3p @305 watt panels aimed south on a single 250/100 for the past 3 years, not an issue yet, 48v.
Click to expand...
The OP has 24V so it will be twice the charge current for the same panels.
 
This is what I do.... In winter, I'm guessing from what I'm seeing here is the max panel output is about 70% of summer output even if they're aimed straight at the sun do to the suns energy diminished passing thru substantially more atmosphere in winter.

So what I've done is permanently connect what panels will equal the chargers max input watts during summer, then I have photo sensor switches that registers the solar intensity & they kick in extra panels as needed via a contactor so that you're always feeding the charger maximum wattage.

In your case for 24v you want a permanent connection to 3000 watts of panels then any extra panels would go thru those solar switches I use with settings staggered so that they kick in at appropriate solar intensities to keep a relatively stable input into the charger. I think I have a video on that switch up on youtube if you want to check it out.
 
Bossrox said:
This is what I do.... In winter, I'm guessing from what I'm seeing here is the max panel output is about 70% of summer output even if they're aimed straight at the sun do to the suns energy diminished passing thru substantially more atmosphere in winter.

So what I've done is permanently connect what panels will equal the chargers max input watts during summer, then I have photo sensor switches that registers the solar intensity & they kick in extra panels as needed via a contactor so that you're always feeding the charger maximum wattage.

In your case for 24v you want a permanent connection to 3000 watts of panels then any extra panels would go thru those solar switches I use with settings staggered so that they kick in at appropriate solar intensities to keep a relatively stable input into the charger. I think I have a video on that switch up on youtube if you want to check it out.
Click to expand...
That's a great way to max your input. I was thinking about doing something like this. Glad to know that I am not alone. I am definitely interested in your setup.
Thanks, for the encouragement.
 
I have a 250|100, so I remember from reading in the datasheet...

If you check out this screenshot of the Datasheet below, Victron shows the 'Nominal PV power, 24V 1a,b'), they show 2900w, and if you read the foot notes for '1a', it says, "If more PV power is connected, the controller will limit input power".

Then if you look at the line for 'Max. PV short circuit current 2', it shows 70a... Then if you read the foot note for '2', it says, "A PV array with a higher short circuit current may damage the controller"...

So that tells me that you can over-panel past the wattage limit they show there, but just make sure the sum of the short circuit current doesn't exceed 70a for the 250|100... (some models come with the MC4 connectors on them, others just have the screw lugs on them, so assuming the 30a limit is for each input connector, if you are using the 250|100 which has the MC4 connectors on them, mine has the screw lugs, so mine just has one set of inputs on it).

Just make absolute sure you don't go over PV voltage of 250v either (assuming you already know that much about it)...



1644895814287.png
 
Last edited:
Samsonite801 said:
Then if you look at the line for 'Max. PV short circuit current 2', it shows 70a... Then if you read the foot note for '2', it says, "A PV array with a higher short circuit current may damage the controller...
Click to expand...
An array with an Isc of 70A would be extraordinary! For an array similar to the OP's, that would be 7 strings combined in parallel.
And even then, the 7 strings would each need to be fused at around 15A, so i would say its an unlikely scenario to feed 70A into an SCC.
 
MisterSandals said:
An array with an Isc of 70A would be extraordinary! For an array similar to the OP's, that would be 7 strings combined in parallel.
And even then, the 7 strings would each need to be fused at around 15A, so i would say its an unlikely scenario to feed 70A into an SCC.
Click to expand...

Well you're not feeding 70A into it, the CC is drawing only the amps it loads the circuit down to (as it reduces the resistance on the circuit), and Victron is saying they can limit input current if you over-panel, they are just saying to keep short circuit amperage number below 70a, probably in case it is doing MPPT sweeps (which are for a brief interval) it can't be possible to draw the current beyond 70a even if it tried to. When it is running at normal cycle drawing maximum power point watts, the amps will be a lot lower, and voltage will be higher on the circuit.

I guess OP could ping Victron if he wants to be sure.
 
Last edited:
Lots of great info here, thanks all for the replies. My conclusion is to just buy another charge controller, but my next question is can I split the power coming from my combiner box? Instead of adding another combiner box? I'm currently only using half of the box max amperage and don't have space to add another unless needed.
 
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