28 replies to this topic

[Esus]

Question:  I do not see an inline fuse in your system description (maybe I overlooked it).  Did you use one (or more) and where did you put it (them)?  

 

Do you have a wiring diagram for your system?

 

Craig,

 

I responded to your PM before I saw this post so I'll copy my reply here as well:

 

Because I wired my panels in series, the 10 awg wire that came pre-installed is vastly sufficient to transmit the most energy the panels could possibly generate, so I opted not to fuse that portion. I probably should have a fuse between the controller and the battery, but again, the wire is really oversized for the length of run and energy that's capable of being produced by the PV. I'm probably just being lazy and I wouldn't tell you not to fuse your setup... but really a PV array of this size can only generate so much energy. Just my two cents. 

 

I had a really nice complex wiring diagram for my last rig, but this one is so simple I never bothered to create one - especially since it's not connected to the truck. Just remember to connect the negative of your solar to the load side of the BMV shunt and not the battery!

 

Cheers,

Eric

[ckent323]

Eric,

 

Thanks for the prompt response.  I ordered most of my parts from PKYS today (free shipping and better price than Amazon).

 

Charge Controller - Victron 75/15

Battery Monitor - Victron BVM-702

VeDirect Cable to monitor - Victron 5M

VE direct to bluetooth - Victron smart dongle

Dc Source Select Switch - Blue Sea 6007

40 Amp Circuit Breaker - Blue Sea 7138 187-40

Busbar - MiniBus 5 x 8-32 Common Bus Bar with Cover - Blue Sea 2314

Dual Power Post 2 x 3/8 Studs - Blue Sea 2017

 

 

Batteries and Panels were bought separately.   I got a slightly lower price with free shipping buying the batteries online from Powerstride instead of buying in person.  I am in Solvang,Calif and they manufacture in and ship from San Dimas, CA about 150 miles from here so I should have them within 10 days or so.

 

Any recommendation on entry gland?  I am looking at the Link Solar roof entry gland.  Alternatively I could drape wires down the back and use a Zamp or equivalent sidewall port (trade off of roof penetration versus wires available for snagging).

 

Also any recommendations on the MC4 connectors and cable? Is one brand as good as another (looking at Renology and Signstek at amazon)?

 

Anything missing?

 

Regards,

 

Craig

Edited by ckent323, 13 July 2017 - 12:49 AM.

[Vic Harder]

That Link solar is nice.  Is it going UNDER your panels or next to them?  I have mine UNDER mine, so I just bought a cheap plastic electronics hobby box, drilled holes in it, two MC4 cable glands, wire nuts, and 3m 4200 to seal it all to the roof under my panel.

 

If you can, lay out all the parts on a piece of cardboard to check placement of components, pre-wire it, and then use your cardboard template to make a base out of wood to mount into your battery box or where-ever you are putting the controller bits.  Best to keep the controller CLOSE to the batteries, as the wire should be short and the temp sensor is in the controller, not on the batteries.

 

Speaking of temp sensor, since you are getting the 702, you have the option of adding battery temp to your battery info...  nice to have.

 

As for missing, are you connecting to the truck charging system?  The Blue Sea ML-ACR is nice!

 

Vic

[ckent323]

Vic,

 

Thanks for your comment!!  I forgot to include the temp sensor to my order. I was able to add it however and avoid shipping cost. ;-)

 

BTW:  I do not plan to connect the camper to the truck.  I may change my mind but before doing that I think I will add more panels (plus whatever is required to accommodate them).

 

I am working on a write-up of my design similar to what you did, but omitting a lot of the investigative stuff that you already did and shared for all of us - THANK YOU!

 

That write up will cover my calculations, questions, decisions and final design.  It references and heavily leverages the work and comments by you Rando, ntsqd, ESUS, and others.

 

Regards,

Craig

[Esus]

Craig,

 

My current rig was pre-wired for solar so I didn't have to do much. I did use a product almost identical to the Link gland on my previous van and although I was a little nervous punching a hole in my roof, it ended up working perfectly. 

 

Looks like you'll be MC4 the whole way so this won't be an issue, but the Renology MC4 to SAE adapter I bought came with the polarity reversed! Based on the Amazon reviews I definitely wasn't the only one. Just something to keep in mind if you plug everything in and nothing works. Fortunately, your Victron controller won't be damaged if this were to occur. 

 

You did mention the possibility of adding more panels later if needed - that 75/15 controller might not be sized to be future proof if so. With my 290 watt setup (3 panels in series) I've already exceed the voltage the 75 v controller could handle. Glad I went with the 100/30. Just a thought. 

 

Definitely put your controller close to the battery like Vic mentioned. Good stuff!

 

Good luck, have fun putting everything together! 

[Vic Harder]

+1 to what Esus just said.  My 75/15 is not big enough to handle the 265w on the roof, about 10% of the time.  The rest of the time it is just fine.  

[michgoblue]

Hey Michgoblue - stoked for you with the Colorado. What a great truck right? Glad my post proved valuable to a fellow Colorado owner!

 

Are your panels wired in series? When you consider all of the collective inefficiencies and real world application, 8 amps seems pretty reasonable. My 290w are wired in series and I get about 10a in direct sun. Hope that helps. 

 

Yeah I love the Colorado.  It drives so nice I forget it is a truck (and how long it is).  I put my panels in parallel but can pretty easily switch them back.  I have a MPPT controller and tested them both ways and really didn't see a difference.

 

Anyway thanks again for the info and good to hear my 8 amps is not so far off what I should expect - its just a lot less than the rating!  When I had 3 x 120W panels on my old camper I thought I got more amps, but it may have also been conditions - lots of clouds and shade last couple of times I have been out.

[Esus]

Yeah I love the Colorado.  It drives so nice I forget it is a truck (and how long it is).  I put my panels in parallel but can pretty easily switch them back.  I have a MPPT controller and tested them both ways and really didn't see a difference.

 

Anyway thanks again for the info and good to hear my 8 amps is not so far off what I should expect - its just a lot less than the rating!  When I had 3 x 120W panels on my old camper I thought I got more amps, but it may have also been conditions - lots of clouds and shade last couple of times I have been out.

 

It really does ride nice. With the riser in the front, the bags at 5 psi when the camper is not on, and E rated tires that are slightly larger than the stock size, mine seems a lot more like a truck now. Still a great ride though. 

 

The reason I asked about series vs parallel is that I would expect you to see more amps in parallel. Parallel keeps the voltage the same and multiplies amps. With two panels, I would expect you to see something close to 20, not 10. Assuming your panels are in the 120 watt range. 120w/12v = 10a. In parallel you multiply amps by number of panels. In series you'd remain at 10a but double the voltage. 

[Vic Harder]

Vic,

 

Thanks for your comment!! 

 

BTW:  I do not plan to connect the camper to the truck.  I may change my mind but before doing that I think I will add more panels (plus whatever is required to accommodate them).

 

It adds a whole lot of complexity to connect the two, but also adds a lot of flexibility.  I have yet to find the time to do a trip report or post much info on the success of my build after my first 4 week excursion, but it is working beautifully.

 

With my 225AH batteries, I have yet to see more than 8% draw down overnight.  Meaning I get up in the morning and the batteries are still at 92% or more.  I did let the batteries discharge 3 days in a row without solar and got to 80%.  (Southern Utah this May was not too hot.. so fridge and fan got less of a workout than you might expect).

 

I added a Blue Sea voltmeter and ammeter in the cab of the truck so I can monitor what is happening to both the camper and truck batteries, and how much current is flowing between them.  I also have the Blue Sea 7622 and remote switch that allows me to connect/disconnect the two battery banks remotely.

 

That allows me to say that, after that discharge to 80% (45Ah) , I went for a drive and then the alternator started pumped 55A into the camper batteries with only about .4v voltage drop from alternator to camper.  Woot!  

 

Long and short of it, if I didn't have solar I could recharge a 3 day discharge in a bit over one hour of driving.

 

I'm happy!

[Esus]

I hear ya Vic. When I drove the Pan Am I had a voltage sensitive relay with a toggle switch and volt meter wired to the dash and large wires from the engine battery to the relay in the van. I only had 200 watts of solar and as we all know, heat and humidity are the enemy of solar. As such, in Central America I relied heavily on the occasional drive to recharge when the fridge was really cranking in that crazy heat (not to mention cranking the fantastic fan every night). That setup was great because we were constantly plugging away at the drive. Conversely, in my current rig, in the Rocky Mountains and surrounding deserts, where I often park in one spot for days, I opted for pure solar. It's so cheap and easy these days. I can sit at Indian Creek for weeks without so much as turning the ignition key! Assuming I have a cohort to drive to the cliffs...