Working out the kinks in solar system.

[yorkj2006]

So I've recently been trying to set up a solar system to my lifep04 batteries in my new intech flyer discover but even tho I *think I'm wired up correctly I don't seem to be getting any charge to my batteries during the day. I've got a long trip at the end of August and I'd like to be capable of being fully off grid the entire time except for when I drive from one location to the other.

My setup is 300 watts of 12 v panels on my roof and 100 watt via solar suitcase so I can chase the sun. The 300 with on the roof (renogy eclipse) go into a victron bluesolar mppt then to a Busbars then batteries. The suitcase (renogy eclipse) has a built-in pump charge controller that hooks up via sae connector that came with trailer which goes to the Buspar then batteries. I'll post my hand-written diagram (may not be worth looking at), but I just don't know what I'm missing (other than some fuses). Any ideas?

 

[yorkj2006]

 

[yorkj2006]

 

[yorkj2006]

You can see the times on the pics above. The first was 1220 in the afternoon in partial shade but solar suitcase in full sun. also as I plugged in the suitcase I watched my battery monitor to see if I went from - watts to positive but nothing changed at all. System stayed at roughly a 4.25- 4.5 amp draw. Second is this morning a few minutes ago which basically proves that for the rest of the day yesterday no energy was added back into my system. I'm hoping one of the solar gurus on here will see something stupid that I missed!!!! Be gentle... it's my first time.

 

[sackettmw]

The shunt should be the only thing connected to the ground post of the house battery. All other connection go on the other side of the shunt. Otherwise your meter is not reading everything.

 

[burleyman]

It appears your shunt may only be passing current from the suitcase panel, and the current shown is an average 100 watt panel output. It also appears no current from the permanent panels is going through the shunt because of the wire from the far right side of the negative bus bar to the negative of the batteries.

A clip-on DC ammeter is handy for troubleshooting.

 

[yorkj2006]

The shunt should be the only thing connected to the ground post of the house battery. All other connection go on the other side of the shunt. Otherwise your meter is not reading everything.

So I need to connect the dc electrical system terminal to the negative bus bar? And not the common ground Going to the chasi? This is kind of making sense but I don't have that ah ha moment yet where I actually understand what I've done wrong ?

 

[yorkj2006]

Pulled this from the victron website to give myself a visual... this is what I mean .... I think.

 

[sackettmw]

So I need to connect the dc electrical system terminal to the negative bus bar? And not the common ground Going to the chasi? This is kind of making sense but I don't have that ah ha moment yet where I actually understand what I've done wrong ?

You need to remove all connections from the negative terminals of the house batteries except for the battery side of the shunt and the wire connecting the two batteries together. Everything else can go to the chassis or the chassis side connection on the shunt. It doesn't really matter where.

 

[Alloy]

Disconnects for the batteries and solar

 

[yorkj2006]

I'm at work so I can't put this into practice till tonight, but I drew out another diagram that I think puts what your saying into practice. Nothing touches the battery terminals except the cables connecting the 2 batteries together, the cables from the + bus bar to the + batteries and the - battery terminal to the shunt to the - bus bar to the chassis. Ignore the dark black lines with x's over it.

 

[sackettmw]

I'm at work so I can't put this into practice till tonight, but I drew out another diagram that I think puts what your saying into practice. Nothing touches the battery terminals except the cables connecting the 2 batteries together, the cables from the + bus bar to the + batteries and the - battery terminal to the shunt to the - bus bar to the chassis. Ignore the dark black lines with x's over it.View attachment 674185

Looks right

 

[yorkj2006]

When i got home last night I was able to change my connections to reflect the above diagram. Seems to have partially fixed my issue. I can now see my "solar suitcase" when its getting sun and connected to sae port. I'm not however able to "see" my 300 watts of solar thats on the roof and wired directly to the busbars "via the mppt". I've read today that the victron mppt needs a voltage 5 volts higher than the battery voltage to initiate charging. The panels I have 17.7 volts of operating current, with 3 wired together in parallel running through a 50ft 10awg to the controller ( I'll cut it down when I do my final instal); so I'm assuming there is a decent voltage drop from that. By wiring them in series rather than parallel that should fix my voltage issue allowing the controller to work I hope. Hopefully that's it and I can do a final install and move on to the next thing. Any other glaring issues with this plan?

Thanks for all the input. My headache is slightly better already!!!

 

[NatersXJ6]

You seem to have hit on it yourself, but I would change the panels to series and I’m guessing that will make a difference. When I chose my Victron MPPT (75/15). I read the stuff about needing 5 excess volts to initiate. I have 2 panels at 100W each, and it is fairly common for the combination to only hit 31-33V. I’m guessing you aren’t getting enough volts to initiation parallel configuration. Please note that I’m a rank amateur, so there are many opinions on this site that should carry more weight than mine, but you could easily check the panel voltage under sun with a multimeter.

 

[calicamper]

So I've recently been trying to set up a solar system to my lifep04 batteries in my new intech flyer discover but even tho I *think I'm wired up correctly I don't seem to be getting any charge to my batteries during the day. I've got a long trip at the end of August and I'd like to be capable of being fully off grid the entire time except for when I drive from one location to the other.

My setup is 300 watts of 12 v panels on my roof and 100 watt via solar suitcase so I can chase the sun. The 300 with on the roof (renogy eclipse) go into a victron bluesolar mppt then to a Busbars then batteries. The suitcase (renogy eclipse) has a built-in pump charge controller that hooks up via sae connector that came with trailer which goes to the Buspar then batteries. I'll post my hand-written diagram (may not be worth looking at), but I just don't know what I'm missing (other than some fuses). Any ideas?

All the controllers I know of need stand alone wired directly to the battery otherwise you mess up the voltage monitoring ability and they don’t charge the battery correctly. No reason to tie them to the bus bars which are tied to other stuff and will no doubt cause voltage monitoring issues with the controller ?