9 replies to this topic

[buckland]

I was not wanting to start a new topic as I have but one question but hunted and could not find an answer.

Soooooo 

I have a portable 90 watt panel. I installed a wall mounted plug on drivers side  and wired it through to the 2 glass mat batteries which are side by side + to + and - to - wired. This through the Morning star 6 controller. Has worked great for years.  I just now bought a 160 watt panel I will mount to the Yakima rack channels on the roof. I installed the FWC plug in the roof today and will wire through to the battery compartment tomorrow.  I bought the Morningstar 20L for this panel. I decide it was more economical to buy this and use the other 6  for the 90 watt panel then to buy bigger controller for both.  So I am about to install the controller for the roof top panel in the battery box area. I will wire the new panel to the controller and then wire the controller to the first battery (which is connected to the second battery)

My concern....and so question is ....is that okay?.... Can I have one panel on one controller and the other on the new controller and both feed into my batteries which are connected + to + and - to -?

I just hate fire.... in the camper electrics.... I have an inline fuse as well on battery.

 

Love to know before I try it out.

 

And thanks

[Squatch]

Your battery wiring is called "Parallel wiring" which essentially makes a bigger 12 volt battery. As opposed to "Series wiring" which makes a 24 volt battery. Red cable to +, - to other +, - to black cable.

 

I don't think your set up will be dangerous. But I think I would prefer to have both panels going into one larger controller. That way you don't have 2 controllers competing to accomplish the same goal. Plus it would simplify the system.

 

You can always use that 2nd controller with the portable panel to do other things like charge car, boat batteries ect. Mobile battery charger.

 

I'm starting on my system now. I'll be set up so that both the roof panel and the optional portable will feed into the same SC2030 charge controller. The panels will be wired parallel. So the additional panel if needed will just add more amps to the charging process.

Edited by Squatch, 15 August 2016 - 06:22 PM.

[buckland]

Gotcha...I think. Not sure if the two controllers would be competing,,, wouldn't one simply work at its peak output to fill both batteries and the second be doing the same and when the batteries are charged they both do as if they were solo? The reason is I have the 20L already and still have the 6 so why not use both. Just the 20L is not enough to handle the 160 watt and the 90 watt portable at the same time. Either way I am happy to have gotten the 160 panel... just that more juice on a cloudy day.

thanks for the input.

[cdbrow1]

Gotcha...I think. Not sure if the two controllers would be competing,,, wouldn't one simply work at its peak output to fill both batteries and the second be doing the same and when the batteries are charged they both do as if they were solo? The reason is I have the 20L already and still have the 6 so why not use both. Just the 20L is not enough to handle the 160 watt and the 90 watt portable at the same time. Either way I am happy to have gotten the 160 panel... just that more juice on a cloudy day.

thanks for the input.

 

 

What happens when the "compete" is that one controller raises the voltage the second controller sees from the battery - therefore the second controller thinks the batter is more charged than it is so the second controller reduces it's charge rate to prevent over charging.  The end result is that you don't get the full benefit of all the panels. Same thing happens when you leave the solar on when the engine is running. It's not harmful - but it is also not optimal. 

[buckland]

Okay .... then if I have one panel wired to the 6 and then it is wired to the first battery....and the other panel wired to the 20L and it also wired to the first battery....won't they both be monitoring the same voltage in the battery and charging it as they would singly? ( as you might have figured I am not a wiz at electrics ...just the basics). The two controllers wouldn't be wired together other than the output to battery.

 

Just thought it would be nice to have 250 watts available but only in a pinch. I should think the rooftop 160 would suffice (I have an Engle  fridge and LED lights. Then at times when power is low from days of clouds the portable 90 would be plugged in (so the 6 controller would not be functioning most the time ...

Edited by buckland, 15 August 2016 - 11:59 PM.

[DesertDave]

I think the 'not optimal' commentary is, while technically correct, not practically a serious concern.  What the OP describes is just like what a lot of folks do when they add on a portable panel that has it's own controller.  Adding 90 watts to the 160, when the user determines the need is there, will add charging capacity. 

 

Some people use the point that a portable can be placed into the sun, or can be moved to track the sun, while the roof-mounted panel might be shaded or in a sub-optimal situation.  I think this type of situation is how the OP wants to use theirs.  I don't see a major reason to go fund an additional controller.

[buckland]

Okay then! Thanks to all input ... feel better not to cause more headaches at my own hands. I will wire it up and motor on. 

[buckland]

Hey there... have the plug installed on the roof wired through.

 

1.   On the plug FWC sent me, the corrugated wire side (female... right side in photo ) is the Red positive (correct?)

 

2.   On the plug I am to cut off and splice on the FWC plug ... is the plug on the right with the red stripe on it Positive?

 

This is the Solar BLVD 160  W panel.

Attached Thumbnails

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Edited by buckland, 19 August 2016 - 06:34 PM.

[Squatch]

Set the panel in the sun. Touch the contacts with a digital volt meter. If it reads voltage then red is connected to positive out from panel.

 

If you get a - sign in front of your voltage readout you have them backwards.

[buckland]

Sur-in you're a saint and a scholar... much obliged ... I'll get my meter post haste.