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Wire 2 solar panels of different wattage
- Thread starter Choco
- Start date
No you can't wire them together. Presumably they have different terminal voltages, which if wired in parallel would mean the stronger voltage will try to oppose the lower voltage, and could damage one or both panels.
However you can get solar controllers that will accept panels of different voltage and will combine the best of both.
However you can get solar controllers that will accept panels of different voltage and will combine the best of both.
I don't often disagree with the Prof, but there isn't a blanket yes/no answer. It certainly DOES depend on the type of solar controller fitted. Most vans will be fitted with a pulsed wave modulation (PWM) controller. Some PWM controllers have two inputs, and in that case you CAN connect both panels. But the best efficiency would be derived from using a maximum power point controller (MPPT). with an MPPT, panels are connected in series resulting in the voltage of the panels being added together giving around 35-45 Volts. The MPPT stages this down appropriately for the battery connected, and acts as a smart charger would.
Your controller will be located in an upper level cupboard somewhere internally in the van
Your controller will be located in an upper level cupboard somewhere internally in the van
Unless you are draining the battery to 20% every day it's very unlikely that you will ever need the extra 80 watts, not that you will get that if you try and combine it with the 200 watt panel.
Far better off just fitting the 200 and flogging the 80w in eBay and using the money towards a good (Victron) MPPT controller.
I only have 130 watts and rarely have to resort to charging from EHU.
Far better off just fitting the 200 and flogging the 80w in eBay and using the money towards a good (Victron) MPPT controller.
I only have 130 watts and rarely have to resort to charging from EHU.
I hate to differ , most so called 12V solar panels have an off load voltage of 21 volts and a maximum power output at about 18V which the controller takes in and drops it down to charge the 12V battery.Also unlike batteries, solar panels of different wattages and voltages do not have a large reverse current ( i.e current flowing into them from a larger voltage source) and can be connected in parallel with absolutely no issues. The same can be said of two identical panels , one in full sun,which will have a high output voltage and current, and the other in full shade, which will have a low output voltage and very low current.the higher voltage will not drive current into the lower voltage one, the two merely contribute to the controller whatever current they can
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Interesting. I use 2 suitcase panels, 1 x 50 watts and 1 x 100 watts each with their own controller.
I set them up with the 50 facing East and the 100 facing West. That way they don't need constant moving around to follow the sun.
To me the advantage of suitcase style panels is the ability to save weight and leave them at home when on EHU.
I set them up with the 50 facing East and the 100 facing West. That way they don't need constant moving around to follow the sun.
To me the advantage of suitcase style panels is the ability to save weight and leave them at home when on EHU.
That will be dependant on the units you are trying to parallel together. You would need to check their compatibility.
Different Wattage Solar Panels Wired in Series:
If mixed wattage solar panels are connected in series, the total voltages are added. But the amps are reduced to the current of the lowest panel.
Wiring Different Wattage Solar Panels in Parallel:
If mixed wattage solar panels are connected in parallel, the total amps are added, but the voltage of the system reduces to the voltage of the lowest panel.
A good article Here
It's your call😉
If mixed wattage solar panels are connected in series, the total voltages are added. But the amps are reduced to the current of the lowest panel.
Wiring Different Wattage Solar Panels in Parallel:
If mixed wattage solar panels are connected in parallel, the total amps are added, but the voltage of the system reduces to the voltage of the lowest panel.
A good article Here
It's your call😉
