Victron SmartShunt

Explorers2

Today I will mount a Victron 100/20 controller in the space under the port side seat, connecting existing wiring to solar panel and battery. I’m working out how to wire up the Victron SmartShunt that will arrive in a few days. Through meter testing, it looks like the wires that come from the solar controller go straight to the battery. So my plan is to wire the shunt into the negative side battery wire coming from the controller, and then mount the shunt beside the solar controller. Does anyone see any issue with that plan? Seems like it would be a clean install with no weather issues. 

skibug

All negative wires for the battery need to terminate on the load minus side of the shunt and then one wire should go from the battery minus side
of the shunt to the battery negative terminal. It probably makes more sense to late the shunt closer to the battery minus side.

Basil48192

I just found this old diagram in my files.  What size is the negative wire from the controller?  I ended up using a negative bus bar to clean up the wiring.  

TourDeForth

I just installed the Victron BVM-712 smart shunt in my tab 320s. As a stated by skibug above “All negative wires for the battery need to terminate on the load minus side of the shunt” I ran across one piece of advice I found on an Australian overlander website which is to install the shunt close to your batteries to keep the leads short and minimize voltage losses in the wiring to the shunt. Granted the Tab 320 is very small so you won’t really be that far from the batteries no matter where you place the shunt.

Explorers2

Okay thanks. I was trying to deal w the water / weather issue but I see I’ll need to mount it up by the battery. I’ll figure out how to protect it from water. Thanks for the added info. 

Right now I’m strategizing on how to get those 10ga wires cleanly into those tiny holes in the 100/20! Ha! Nothing is ever easy in DIY Land! 

TourDeForth

I ran into the issue of trying to squeeze 10 gauge wire into those tiny holes on the solar controller. First I tried twisting them tightly and insert them carefully, nope, wires kept fraying spilling out. Then I bought a ferrule set (been wanting one anyway) but couldn’t find a pin that fit 10 gauge wire and crimp down small enough to fit in the controller. I got a wild idea and ended up tinning the wire ends with just solder and then using the ferrule crimper on that, lol! It worked but took a few squeezes…

Explorers2

This works -> clean cut w good wire cutter. Trim 1/8” only with sharp wire stripper. Don’t do anything to the ends, no twisting or mashing,
just insert them into the little holes. They go right in up to the trimmed insulator. Pull firmly once screwed down to confirm tight joint. Clean install. 

Explorers2

Explorers2

All done w 100/20 install. Works great 

Do you guys know what gauge wire I will need from the shunt to neg battery terminal? I thought I’d make that up in advance. 

AnOldUR

@Explorers2 That would depend on the loads going to the battery and the length of the wire between the shunt and battery. For instance, if you have an inverter that draws a high current, you’d need a minimum of the same wire size feeding the inverter.

elbolillo

TourDeForth said:

I ran into the issue of trying to squeeze 10 gauge wire into those tiny holes on the solar controller. First I tried twisting them tightly and insert them carefully, nope, wires kept fraying spilling out. Then I bought a ferrule set (been wanting one anyway) but couldn’t find a pin that fit 10 gauge wire and crimp down small enough to fit in the controller. I got a wild idea and ended up tinning the wire ends with just solder and then using the ferrule crimper on that, lol! It worked but took a few squeezes…

I am suprised that you had issues with 10 awg wire. My two solar chargers are wired to the battery using 8 awg wire. I had no issues whatsoever inserting the wire into the solar controller.

TourDeForth

I used 10 gauge zip wire from Powerwerx to run to my new battery location under the bed next to the air conditioner. The wire strands seemed a little thicker than what I’m used to with 10 gauge wire.