Solar Panel Wiring

[Kist]

Hi,
I was wondering if someone out there might be able to help me with a question regarding parallel wiring of solar panels. I have 2 Siemens 75 watt panels on my boat now wired in parallel going to a 25 amp charge controller. I recently acquired a Siemens 50 watt panel and would like to wire this in parralel with the 2 75 watt panels. Can this be done or do I need to wire the 50 watt panel in seperate from the other two? I would prefer not to install another set of wires if I do not need to. Thanks for your help.
Kevin

[mikefossl]

It would depend on the voltage of the panels involved. 12v panels have different actual open circuit voltages which should be close to be used in parallel. Personally I like the idea of using identical panel sets, each going to their own charge controller but I'm no expert.

[forsailbyowner]

I have 2 180 watt panels wired in parallel with four 75 watt panels. just have a diode on each. dont see a problem

[senormechanico]

As previously stated, as long as the open circuit voltage ratings are reasonably similar, no problem wiring them in parallel.

[Bash]

I've done it without problems. While you can get by with it when the voltages are similar, identical panels are more idea.

[s/v Jedi]

I would assume that the wiring in place now is too small to add the extra amps from the new panel. So you probably need to either replace it with larger diameter wire, or add separate wiring for the new panel.

cheers,
Nick.

[Kist]

Thanks for the information everybody. It sounds like wiring them all in parallel is not the most effecient way of doing it but it will work and that is what I was wondering. I think the 10 gauge wiring I installed for the 2 75 watt panels will be big enough to handle the amperage from all three panels. The output of the 50 watt panel is only 3 amps. Again thanks for all the help.
Kevin