Anyone else running mismatched panels in series on a Victron MPPT — worth it or waste of time?

So I've got two 200W panels on my static that I picked up ages ago, and I managed to grab a used 175W panel cheap off eBay. All three are nominally 12V but the Voc and Isc figures are slightly different across them. Currently running the two matched ones in series into a Victron SmartSolar 100/30 and just leaving the 175W sat doing nothing.

Tempted to wire all three in series but I know the weakest panel drags the whole string down on current. Voc stacks fine — I'm well within the 100V input limit — but I'm wondering if in practice the power loss is as bad as the theory suggests, or if it's one of those things where real-world results are "good enough."

The alternative is running the 175W into a second cheap PWM controller I've got kicking about, but that feels like a bodge and I'd rather keep it tidy. Seen some folk suggest a second MPPT input but that's money I haven't got right now.

Has anyone actually measured the difference on a setup like this? Curious what the Victron history graphs looked like before and after if you've done it.

@OffGridDawn the key thing to understand with mismatched panels in series is that the current gets limited to the lowest panel's Isc across the whole string. So that 175W panel will drag down the output of your two 200W panels if its short-circuit current is lower.

Before wiring anything, compare the Isc figures on the datasheets rather than the wattage ratings. If the 175W panel has a notably lower Isc (say 8.5A vs 10A on the 200W panels), you're leaving real money on the table.

On my Ducato build I ran two mismatched panels briefly — the Victron MPPT handled it fine electronically, but the yield loss was measurable in the app. I eventually moved the odd panel to a separate controller.

Worth checking whether your Victron controller supports two independent inputs before spending more on hardware though.

@DucatoSolar is correct about current limiting, but there's another wrinkle worth flagging —

When you wire mismatched panels in series, the voltages add up fine, but the weakest panel's current ceiling pulls everything down. However the real gotcha is if the panels have different temperature coefficients, your Victron MPPT is trying to track a combined IV curve that's... let's say, somewhat irregular. Not impossible, just less efficient.

I ran something similar on my boat — two Renogy 175W alongside a random branded 160W. The MPPT handled it, but I reckon I was losing maybe 10-15% compared to what the figures should have given me.

Honestly for a static setup I'd probably wire the two matched 200W panels in series and put the 175W on a separate string if your controller has dual MPPT inputs. The SmartSolar 100/30 onwards can do this.