Journey Updating solar setup...

[Hitting the road]

When I was away last week off grid for a few days, I put the meter on to the existing panel on the roof and couldn't get more than 0.2 amps reading of power going in to the MPPT from that panel. I should have seen maybe 5amps or so on a good day, as the panel would have to be around 7amp I would have thought. (150w divided by 20 volts = 7.5amp).
That said, if the batteries were close to fully charged the MPPT may have been pushing back reducing the input? When I put the meter directly in to the panel output with no load, I got some weird readings...just voltage of about 20v and a zero amp output reading. Could have been doing something wrong too...

So...I have finally bitten the bullet and lashed out for 2 new 200w solar panels. They are Sphere by make and were priced pretty well at $199.00 each. The specs appear ok, same physical dimensions as the old 150w or what ever it is currently fitted to the van. The original was ok I guess for topping up the 100amp AGM that same as standard equipment on this model.

To date I have been carrying 2 x 200w (supposedly) folding solar panels which I put out as needed...they have worked fine for the past couple of years off grid...and being I had upgraded the batteries to 2 x 135 amp Lithium I had needed extra to top them up. I have always connected the panels in series, even when I used them with the Camper trailer previously.

Anyway, the plan is to replace the existing panel with a new one, then add the 2nd panel a few feet behind it as there is the space for it. The extra one will add around 11kg to the rear of the roof but won't be right at the back so lifting the pop top shouldn't be any drama. I am in the process of removing the struts to have them tested and regassed in necessary....the roof has been coming down slightly skuiff favoring where I think a strut is a bit weak. They are rated at 650N, I may have them lifted to 700N if that is at all possible.

I have decided to fit the new pair in series, not parallel...and am aware of what happens to output if one panel gets shaded. But majority of the time shading shouldn't be a big problem, though if it does I'll still have the portable panels on board to back up if ever needed. The MPPT is good to 100 volts input so plenty of room to move, given even if I connected all 4 would still only see maybe 80 volts if all gave their 20 volts output capacity.

 

[Drover]

Struts just replace from Gas Strut Guys far better .................................................
Checking for amps is not the same as checking volts but really if your controller has screen it will show you the operating volts/amps readings, .just isolate each panel in turn, but the amps will change with load, which are different than the short circuit readings which you get with panel disconnect from system and testing on the panel terminals themselves or at least the end of the lead, you need to be able to know whats on the panel label to know what the readings should be in the lab............ I used a remote cam... then you can do the math that needs to be done and if it doesn't match up the differences usually mean nothing at all when it all boils down as you will never get the lab readings, ever ...

I find my panels voltage and amp output will vary from .4 to 20a and volts from 15 to 18v all depending on what the MPPT wants, if I throw more load on the system the draw from the panels increases, I too had a wonder about output so loaded everything up and saw no need to replace things ... My 200w panel doesn't look great but at 13 yrs old is still reading figures it did when I first tested it ....................... Still haven't been convinced series is better than parrellel and I can plug in the portable if needed without stuffing around................. My max amps on paper could be in the 31-34 amp district depending on voltage..... best Ive seen is i think 18 but usually 12-14, not for very long, just chugs along at 4 maby if I see it up high for too long I start to do checks as something is astray..

On a good sunny day at about 1100 I plugged my fridge anderson on van via a jumper into the van 12v output anderson and turned the fridge on, a wonderful way to see how your system can handle a really good load, while I was expecting to see heaps of amps from the panel I didn't the MPPT just increased the feed so the battery stayed at 100% and the fridge was fired up, ran for a few hours and it worked just not how I thought it would the battery didn't know it was there until I shut down the panels then the numbers changed................... I was hoping to see massive amounts of solar power, I didn't, have always been going to do it again but this time have the panel cables handy and just have one at a time plugged in to see what happens then................

 

[Hitting the road]

Yeah, I did scroll through the readings, but figured the MPPT was affecting what the panels were "allowed" to send..."Maximum Power Point Tracking"...says it all really...

I found new struts on line for $27.50 each delivered from Gas Strut Guys as suggested...825mm x 630N so have ordered 4. The old ones were a bit tatty with some rust around the ends anyway...much happier putting new ones in. That hopefully should fix the slightly saggy front left of the roof I was seeing...

 

[Drover]

I have used them for many years van and Jeep, I did a write up once on how to change the roof struts and not rip your arm off or catapult yourself across the yard....................... I would also give the shafts a rub over with sheep dip a few times a year to clean any crud off so they didn't jam or chew seals, seemed to have worked...

Yep, your panels seem to do the same as mine, today I hooked up my air compressor to the van to see if its fixable, wow now they really give the system a work out more than the fridge........ It all looked okay, not so the compressor its in the bin and one from Kings in the mail..

 

[Hitting the road]

Lol...I used a small ratchet tie down thingamebob to retract the struts taking pressure off the mounts so they just fall out...will do the reverse to put the new ones back in.
I have used a Thumper 12v compressor for years now with no dramas, I think I bought it originally from Kings. I also have a brand new one unused ready as a back up in case it lets me down one day...

 

[Drover]

I had one pop off on a trip years and years ago, standing on a ladder trying to compress it by hand enough I nearly catapulted myself over the vehicle, so I sat down, had a beer and grabbed a strap and sorted it out, amazed I didn't think of it earlier, it was then a effortless job but I was amazed at how many other campers thought I had invented something magic ............ my compressor was bought sometime just after the turn of the century...