mixing panels on one controler

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Not ideal i all ready know but my system is being rearanged. I will have a 40V oc 330W panel controlled by its own votronics controller.
i have a 100W 19?V polycrystaline and 120W 22V monocrystaline panel. I can connect these outside either parralel or series what agravation can you see? Not optimal but i would have agravation putting another controller in the existing location. If push comes to shove will ignore the poly. Just to add agro the second controller is only 10 A so initial plan is to only add it in spring autumn ie off in summer. May eventualy get another controller but 450W in summer should be enough.
 
Making an assumption, that combined the "nominal" voltage would be controlled by the 22V panel? Max output would be at 10amps. (potentially). That is risk running on a 10amp controller. I blew at 20A controller on my last M-H. With just 200W of solar on the roof. During the recent Warm spell I was seeing 24+Volts regularly. I have a Voltmeter conected to show the actual panel voltages.
 
The 10 amp controller should be able to handle the two panels at 220w,

OOPs sorry ignore that the maths in my head didn't work, as above it could be a bit too much (y)

Martin
 
thanks for replying,
the spec of the 120W panel states 6.9 A i know 10A is not enough in summer hence my comment about using in spring Autumn (unplugging the fuse). This would preclude using in series as the current would be too much (buy another controller) the poly being a lower voltage (cant remember precisely what) would bring the volts down ie total power less than achieved withg 2 controllers.

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Why not just wire them both in parallel (+ to +, -to -). Flat on the roof they would be most unlikely to yield more than 70% of the nominal power, and there would be some inefficiency because of the small voltage difference. You'd be unlikely to get more than 12 amps in the best conditions. Solar controllers generally just waste extra power safely, if there's not a huge overload.
 

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