Solar Controller Heat/Location

[Windjammingnc]

Currently, I have 200W of Panels that are just placed on the ground for optimal Angle/location. The Panels feed an MPPT controller that is mounted in the trailer with the output of the controller connected to a fused location in the Converter Panel to charge the batteries. I've noticed that when the solar is putting out almost max. wattage, there is some significant voltage drop between the controller and the batteries (about 0.5v)..

Recently, I purchased another 100W of panels and need to upgrade the MPPT controller to support the additional wattage. I really want to mount the controller closer to the batteries and was wondering how much heat gets dissipated by the controller (the heat sinks are pretty large).. I want to mount it in the area of the V-Nose where the propane tanks are located so that I only have a short run of heavy gauge wire to the batteries.

Any thoughts would be appreciated.

[Rich.M]

More important to have the right gauge of wire between the controller and batteries. I assume you are wired series to take advantage of the mppt controller. Gauge won't be a problem from panel to controller. Controller output will be charging voltage at higher amps . Run 6 gauge from the controller to the batteries with the 300 watt system and losses should be minimal for most wire runs between. I would not place the electrical in with the propane tanks. Too much chance of going boom.

[Windjammingnc]

Yes, the panels are in series to minimize voltage drop. Likely, until panels go on the roof, I'll have to connect the output of the controller to the panel for now. I'd have to drill another hole from the kitchen to the propane area to reach the batteries.

[Windjammingnc]

I will likely upgrade the gauge of the wire from the controller to the fuse panel - it's 10 gauge now. I can't recall what gauge wire FR has from the Panel to the batteries but our panel is at least within about 6 feet of the batteries and the controller is about 3 feet of wire length from the panel.

[Skyliner]

I've never really noticed much heat coming out of my controller but I really didn't care if it did pump heat out. My controller is mounted within 3 feet of my batteries.

Don't forget to move your converter within a couple feet of your batteries either. Does no good being so far away from the bank and you may never get into bulk mode charging due to voltage losses.