Micro Minnie FLX solar and battery

[creativepart]

You are 200 miles from the Canadian border - so, that's going to effect solar output compared to Arizona, etc which would be closer to the max expected output in the middle of summer on a very sunny day.

14amps is ~140w from your 400 watt PV system. That does seem like perhaps one panel is either unplugged or not outputting power. It would require accessing the roof, but you can put a voltmeter on each of the MC4 or SAE connectors feeding the panels into the combiner box on the roof. Each should put out about 18-22 volts in full sun. If one doesn't then you'll need to see if it's a panel issue or a wiring issue.

I have a 300w system and I almost never see above 225 watts peak at any one time. My Victron shows me total amount of watt hours and the peak wattage seen each day. I like to see above 200w peak because then I know each of the three 100w panels is putting out power. But I live in South Texas and travel to New Mexico and Arizona a lot, too.

I wish I knew more about the FLX, but on most RVs the solar charge controller is directly connected to the batteries and it will charge those batteries even when the battery disconnect is off. So, if I was charging up for a trip and I couldn't plug into shore power to prepare, I'd turn off the battery disconnect so 100% of the solar output would charge the batteries.

But in reality, I'd plug the TT into a 110v outlet, and turn on the fridge to both charge the Lithionics battery to 100% and to chill the fridge before loading it. I'd not rely on solar for those tasks while parked at my home for loading.

[Marine359]

To check Voc
Go up on the roof and disconnect the panel mc4 connectors from the gland, or whatever they are connected to. Use a a voltmeter or multimeter between each panel’s mc4 connectors placing probes in the negative mc4 and the positive mc4. Do this with both panels. Record your measurements. The measurements should be done when there is sun, but it doesn’t have to be a real sunny day.
After reconnecting the mc4 connectors, turn everything off in the trailer, and record the battery voltage, and watts produced on your solar charge controller. Maybe your Lithionics app can give you the same info.
Theses e measures will tell you if your solar array is working properly. Compare your Voc measurements to manufacturer spec. Your measures need to be within 10% of spec. Some panels have higher Voc than others. Example, my 100w panels have a Voc of 32vdc..

[creativepart]

Originally Posted by Marine359

TExample, my 100w panels have a Voc of 32vdc..

Jim, you have 24v nominal panels? I'm a bit surprised. 12v nominal are much more common on RV roofs. 24v nominals work at about 32v and 12v nominals work at around 18 volts.

[Marine359]

I have 3x CIGS panels. They are non monocrystalline design, and they do not have a cell structure like normal panels. The voltages are very high compared to hard panels. But they work great. The only downside is that I max out my 100/30 controller when I connect them in series, so I have to go S/P to add a fourth panel. I did a review on these panels.

[creativepart]

Originally Posted by Marine359

I did a review on these panels.

Of course, I remember now. I didn't remember who had the SIGs and nor did I remember that they are higher voltage.

Certainly, the FLX doesn't come with SIGs panels at this point. Those are still a newer technology. Most if not all RVs that come from the factory with PV panels will come with more common Silicon-based Crystalline panels.

[Marine359]

Right.
OP needs to know manufacturer spec Voc for his panels. If he can’t find that in his manuals, he probably won’t want to remove a panel to see the label. Hopefully, this is information you can get be calling WBGO customer service. If he measures Voc within 10% of spec, the problem is not with the panels. So next step is to check readings from Charge controller. If those are out of whack, I’ll put my money on wiring problems.

[Old Navy]

Originally Posted by Marine359

To check Voc
Go up on the roof and disconnect the panel mc4 connectors from the gland, or whatever they are connected to. Use a a voltmeter or multimeter between each panel’s mc4 connectors placing probes in the negative mc4 and the positive mc4.

I don't have an FLX, but from pictures I've seen, the GoPower charge controller remote displays SCC voltage in. I've also read here that the FLX "solar on the side" input is connected to the SCC input, so a multimeter there should give an accurate panel voltage. With 2 panels in series, somewhere around 40VDC. I'm not sure disconnecting the panels and measuring VOC adds any value if the voltage at the SCC input is good.

[Marine359]

The only way to measure Voc is across the panel mc4 connectors. Measuring anywhere else will not give you Voc. And how do you know if the input voltage at the SCC is “good”? What is “good”? Is it some approximation of rated Vmp. If so, OP needs to know spec for Vmp. Practically speaking though, you just need to know how much array voltage is reaching the SCC. The voltage reading of the SCC is battery voltage, not array voltage, so to measure array voltage you have to place a multimeter across the incoming array cables. Maybe the FLX SCC displays array voltage, but others, like Victron do not. I don’t know if you can get an accurate reading measuring the input side of the SCC when it’s connected to the battery. If the SCC is connected to battery, by definition there is a load on it, which can invalidate other measures. When troubleshooting, it’s just easier and more sound to start at the source (the panels), which takes less than 10 minutes, and work your way down the system until you find something out of spec. I would advise disconnecting the output side of the SCC if the panel Voc is good, then testing the input side of the SCC. There could be a loose wire connection which could be identified at this step. Then measure output side of SCC with array engaged before reconnecting to battery.

[Old Navy]

Originally Posted by Marine359

The only way to measure Voc is across the panel mc4 connectors. Measuring anywhere else will not give you Voc. And how do you know if the input voltage at the SCC is “good”? What is “good”? Is it some approximation of rated Vmp. If so, OP needs to know spec for Vmp. Practically speaking though, you just need to know how much array voltage is reaching the SCC. The voltage reading of the SCC is battery voltage, not array voltage, so to measure array voltage you have to place a multimeter across the incoming array cables. Maybe the FLX SCC displays array voltage, but others, like Victron do not. I don’t know if you can get an accurate reading measuring the input side of the SCC when it’s connected to the battery. If the SCC is connected to battery, by definition there is a load on it, which can invalidate other measures. When troubleshooting, it’s just easier and more sound to start at the source (the panels), which takes less than 10 minutes, and work your way down the system until you find something out of spec. I would advise disconnecting the output side of the SCC if the panel Voc is good, then testing the input side of the SCC. There could be a loose wire connection which could be identified at this step. Then measure output side of SCC with array engaged before reconnecting to battery.

From what I gather, the FLX comes with the RV-C Remote Display, which can display a range of values including PV voltage, PV current, Battery voltage and Battery current. That's a nice bit of "built in test equipment". The 190W GoPower panels have a Vmp of 20.4VDC, so for the 2 panels in series, panel voltage at the SCC should be about 40VDC (Vmpx2) on a sunny day, and you can read it right on the SCC Remote. If PV voltage is within range at the SCC, then the panels are likely ok. If I still wanted to measure VOC, I wouldn't climb up on the roof before measuring VOC at the SCC (by disconnecting the + PV input). With no current flowing, the voltage will be exactly the same at the SCC as on the roof, unless the wires/connectors are faulty. If VOC was bad at the SCC, then I'd investigate the connections on the roof.

[creativepart]

Originally Posted by Old Navy

so for the 2 panels in series, panel voltage at the SCC should be about 40VDC (Vmpx2) on a sunny day,

Do you have knowledge that the two panels are wired in series? I don’t know otherwise, but would think Winnebago would be more likely to have wired the panels in parallel. Parallel would be best for the use of the external solar port on the side of the TT.

Also Winnebago seems to have changed the solar panels in the past year or so. Early FLX TTs came with 2-190w panels, while newer FLXs now come with 2-200w panels according to the specifications in the brochure.

[Old Navy]

Originally Posted by creativepart

Do you have knowledge that the two panels are wired in series?

Just going by memory of what I've read here. I don't have an FLX, so no first hand knowledge. All the online pics of Winnie FLX SCC remotes seem to show 40ish volts PV voltage. Here's a pic from an FLX for sale:



Here's another:



And another:



First hand knowledge from FLX owners would be best.

[Marine359]

Originally Posted by Old Navy

From what I gather, the FLX comes with the RV-C Remote Display, which can display a range of values including PV voltage, PV current, Battery voltage and Battery current. That's a nice bit of "built in test equipment". The 190W GoPower panels have a Vmp of 20.4VDC, so for the 2 panels in series, panel voltage at the SCC should be about 40VDC (Vmpx2) on a sunny day, and you can read it right on the SCC Remote. If PV voltage is within range at the SCC, then the panels are likely ok. If I still wanted to measure VOC, I wouldn't climb up on the roof before measuring VOC at the SCC (by disconnecting the + PV input). With no current flowing, the voltage will be exactly the same at the SCC as on the roof, unless the wires/connectors are faulty. If VOC was bad at the SCC, then I'd investigate the connections on the roof.

You are correct in every way. Didn’t know the FLX had built in gauges to monitor the array. Pretty cool stuff.

[GRI]

So I can just look on my go power monitor and check sov?

[GRI]

So yesterday at 12 pm I ran the generator to get my battery to 70%. Turned everything off and left. Today at 3:30 I stopped up there and the battery was at 95%. It was 81 degrees out with very little cloud cover. This is what all my gauges read

[Old Navy]

SOV meaning "Solar Voltage"? Yes, assuming you have the remote monitor shown above, you can check Array (solar) voltage, Battery voltage, Array current, Battery charge current (from the SCC). Essentially, the input and output of your Solar Charge Controller. Battery information like State of Charge, current and voltage should be available with Lithionics a phone app

[Old Navy]

Looks like you are getting about 285W from your panels. That's not bad. The MPPT continually adjusts the PV voltage to look for the maximum power point, so being a little low is OK. If you were to disconnect your battery (and loads), the array voltage should be pretty close to VOC of the panels.

[GRI]

Hmm. I’m lost then. I guess I could see lasting 5 days if i never turn the inverter on and never use 110. Saturday I made one pot of coffee. Turned it off after it brewed. Shut the inverter off and only ran the fridge and the occasional water pump and still used 3 times more power than I’d be able to generate through the solar panels.
I even used a battery pack to charge phones and other electronics.

[Old Navy]

Originally Posted by GRI

Hmm. I’m lost then. I guess I could see lasting 5 days if i never turn the inverter on and never use 110. Saturday I made one pot of coffee. Turned it off after it brewed. Shut the inverter off and only ran the fridge and the occasional water pump and still used 3 times more power than I’d be able to generate through the solar panels.
I even used a battery pack to charge phones and other electronics.

The picture of your SCC remote shows you're putting 18 amps into your battery. If you have 4 hours of peak sun a day, that's about 70 amp hours of charge per day. Assuming you are starting with a fully charged battery, 5 days would give you a power budget of 320AH/5 + solar charging of 70AH/day. 320/5 + 70 = 134AH/day. Reducing that to 3 full sun hours a day still gives you well over 100AH/day for 5 days. Of course, you would have to start with a fully charged battery and a fully cold fridge/freezer.

I would be digging into where the power is being consumed, and trying to find ways to avoid unnecessary usage. There are drawbacks to propane fridges, but they do save a lot of (electrical) power. If the fridge is really drawing so much it drains your battery in 5 days, maybe Winnebago made a mistake in switching to DC. Hopefully some of the FLX owners here can weigh in.

[ldfeat]

This may not help, but I have a propane solenoid on my motorhome that consumes amps from battery power continuously whether the RV is plugged into shore power or not. I even purchased a homemade "gizmo" that signicantly reduces the propane switch solenoid amp draw. Good luck. Larry 2014 Reyo P

[Morich]

When folks are looking at getting the max out of battery use, I often see them state they "turned everything off"??
We often get reports on motorized that folks are missing how many things are left on when they turn it all off!!
Do trailers operate the same way on safety equipment? I would assume so as it is a liability thing!
Before KNOWING it is all off I would have to do some vary specific testing and looking for what is happening as there are many things which do not get disconnected with just the battery disconnect switch.
Steps can be a big power hog when we think they are off as they can have a light bulb left burning underneath where we don't see it in the daylight.
CO and propane detectors? Almost sure they would be left on.
Propane solenoids? Maybe?

Without any experience to point to on this new trailer, I would almost bet there are several power draws being missed and that is eating your lunch!
If amp meters, etc are not on hand, one hammerhead way to test is to remove all the drains as currently done, remove the positive cable from the battery and then test resistance to ground through that cable.
If you can measure continuity to ground, that will be a path for current to move from the battery to ground!
I rarely use ampmeters as my multimeter is often way too low to use and but I CAN get voltage and resistance readings easily.
With voltage and resistance, Ohm's law will get the current without a second piece of gear.

Current is voltage divided by resistance but that is only if you want to have a number to put on it when you are actually looking for NONE!