WFCO 8955-LIS converter woes

[Mark J]

Originally Posted by rubicon327

Mark: Wondering if you implemented your wiring upgrades and resolved the flickering light issue?

Yes, I’ve been meaning to circle back here and post an update of what I did/found. And the flickering lights disappeared with these upgrades!

Here’s what I ended up with:

1. New Battleborn 270Ah lithium battery replacing the Escape-provided GoPower 100Ah lithium. I have plans to move the Go Power lithium battery to our 4wheel truck camper which we still own.

2. Installed a Victron Power-In bus bar which I converted to be able to hold MEGA fuses like the Victron Lynx Distributor. This saved a few bucks over buying the Lynx Distributor and was an easy hack.

3. Between the battery and the Victron distributor, I installed a class T 200A fuse and Blue
Sea battery disconnect switch. I eliminated the Escape-provided battery disconnect and the two auto-resetting 30A breakers which were being used to bus together the feeds from the solar charger, the DC-DC and the WFCO converter. These now are separately fused inside the Victron distributor, along with the hot lead to the inverter which has been moved off the battery terminal where it was originally attached with a mega fuse bolted to the terminal.

4. Installed a Victron BMV-712 battery monitor and shunt.

5. I had ordered the 5.0 with a single solar panel, knowing we would want to upgrade to more solar eventually. Eventually came early, as I decided to just get all the wiring done and over with and added four 45W panels plus one 90W panel to the roof for a total of 460W of solar including the original GP 190W panel.

The panels are on three separate 10awg cable runs from the roof. Each set of wires goes to a separate double-pole disconnect switch inside the rear dinette.

The four small panels are configured in series/parallel to a Victron 100/20 MPPT solar controller. The middle 90W panel (located between the Max Fan and the A/C hole—don’t have an A/C installed yet) is wired in parallel along with the external Zamp port to a second Victron 100/20 MPPT. And the original Go Power 190W rear panel gets it’s own Victron 100/20 MPPT controller. The three controllers are able to communicate with each other via Bluetooth and coordinate their charging efforts. I disconnected the original Go Power PWM controller.

Anything worth doing is worth over-doing, right? The solar system is functioning great, though, and by using multiple, smaller panels, I was able to squeeze a fair amount of solar onto the weirdly shaped 5.0 roof without being visually offensive or unduly affecting the aerodynamics. A side benefit is that I still get reasonable solar production even with partial shading on the roof.

Downstream of the controllers, I fused them with Midi fuses and bussed them together to single set of 6awg wires going into the Victron distributor. I could have added a second Victron Lynx instead, but couldn’t find small enough mega fuses. I’ve since found that some folks have figured out how to hack the Victron to accept midi fuses which are available in smaller sizes. That would have cleaned up the installation further. Maybe next time.

I put all this together in my basement shop on a piece of plywood which I mounted into the rear of the U-dinette. This eliminated some working on my knees in the trailer. I also went through the entire WFCO panel and redid all the connections with ferrules and heat shrink, wherever possible. I found many bad crimps, stray wire strands outside the terminal lugs, etc. Not at all impressed with Escape’s electrical work.

I also added two Blue Sea bus bars to corral all the negatives and 12v grounds instead of having everything tapped onto the single ground stud on the back of the WFCO panel (the trailer came with something like 9 ring terminals screwed onto that single post—and some of those ring terminals had two and three wire crimped into each!)

It was a lot of work and not insignificant cost, but I now know how everything is wired and I’ve fixed the flickering lights and the tripping breakers and vastly improved the converter charging. I feel like it was worth it, for me, but if you are not a self learner by nature this could be a bit too much to bite off. I should credit Nate at Explorist.life for his videos and wiring diagrams where I got a lot of ideas about how to approach this.

A couple findings:

The Victron DC-DC was wired 8awg from the positive back to the rear of the trailer, whereas Victron says it should be 6awg. So I fused that line with a 40A fuse just to be safe and figured I would never see any charge current even approaching 40A back at the battery. To my dismay, Escape also failed to run a negative return between the rear of the trailer and the output side of the DC-DC. So there is no way to measure the output of the DC-DC with the Victron shunt. Escape jumpered the two negatives on the DC-DC together so that the negative returns to the 7-pin (input) side. Thus, they turned an isolated DC-DC charger into a non-isolated one.

A second finding was that there are no negative returns coming from the tank heaters. Once again, I can’t directly measure their draw using the Victron shunt, since all loads are supposed to return through the shunt on the negative side of the battery. I can only speculate that they just wired the tank heater negatives to the frame, which is now buried in spray foam. Argh.

I’ll attach a couple photos of the project below. At some point I may make a clean diagram of the work if I get around to it. Right now it’s ski season in Colorado and the storms are rolling in this week. Merry holidays to all.

[Flyfisherdan]

Mark,

Thanks for your reply.

Did you place the MeGA or MIDI fuses close to the battery bank? What type of 60A breaker did you use, and where did you install that? I plan to also upgrade some of the wire nut and crimp connectors with WAGO connectors. The good news, is that my son-in-law is an electrical engineer with Sandia National Lab, so I have a good source for help from him when I tackle this project.

I find it fascinating that Escape installed WFCO 8955 converters rated for 55A that only have breakers/fuses that top out at 30-40A.

Thanks for your help.

Dan

[Mark J]

Originally Posted by Flyfisherdan

Mark,

Thanks for your reply.

Did you place the MeGA or MIDI fuses close to the battery bank? What type of 60A breaker did you use, and where did you install that? I plan to also upgrade some of the wire nut and crimp connectors with WAGO connectors. The good news, is that my son-in-law is an electrical engineer with Sandia National Lab, so I have a good source for help from him when I tackle this project.

I find it fascinating that Escape installed WFCO 8955 converters rated for 55A that only have breakers/fuses that top out at 30-40A.

Thanks for your help.

Dan

Hi Dan,

I didn’t use any breakers in my redo. If you look at the photos above, you can see the Victron Lynx distributor on the left side of the back panel under the rear wall of the dinette. The 60A mega fuse for the converter line is housed in that blue box. From the battery to the Victron lynx is a 2/0 cable that runs through a 200A Class T fuse, the master shutoff switch, and then into the Lynx distributor. The total length of that cable is less than 3 feet. From the distributor to the converter is 6awg which is possibly 4 feet of cable (at most), significantly shorter than the Escape-installed 8awg cable that it replaced. So, in all, less than 7 feet of wire from battery to converter.

I also used Wago connectors when cleaning up some of the Escape wiring and can recommend them.

Hope that answers your questions.

Mark

[oldwave]

Very nice work. Clean and well planned. When I get my Bigfoot I’ll be evaluating the electrical design

[John in Santa Cruz]

I wanna do something a whole lot simpler

i have a Victron SmartSolar 100/30 already on my table, i'm going to get a PD4655L

I was *going* to hook this up with my existing dual flooded GC2's + SmartShunt, and get it working, then add a DC regulator for the light+maxxfan circuit, and then decide what LiFePO4 to get... but. I'm worried about the 14.6V that PD says the 4655 outputs in lithium mode, I'd rather it was 13.9-14.2. which will still charge a LFP to 99%. I don't really like the idea of adding a regulator to the tow vehicle, so maybe with a 360W solar panel, I just disconnect that from everything, leave the emergency brake on the LFP

(some time lapses)

I dunno, I just looked at the rest of Victrons line, which I'd never paid much attention to. I can see you can do quite a lot with them, including build my imaginary solar+ac 12V power center, but they don't have a 55A DC supply, but a lot of what I was looking at seemed to only be 220VAC

[rubicon327]

Originally Posted by Mark J

Yes, I’ve been meaning to circle back here and post an update of what I did/found. And the flickering lights disappeared with these upgrades!

Wow you have been busy! Nice work.

(I’m not sure I completely understand the need for three solar charge controllers versus one. If I have any specific questions as I design a solar system I’ll PM you)

[alanmalk]

Originally Posted by John in Santa Cruz

I wanna do something a whole lot simpler
...

I'm worried about the 14.6V that PD says the 4655 outputs in lithium mode, I'd rather it was 13.9-14.2. which will still charge a LFP to 99%.
...

Here's a thought...
If you only need to drop the voltage by a constant 0.4 to 0.8 V, consider a diode in-line with the supply. A low voltage-high amperage, either traditional silicone, or Schottky, should work just fine depending on how much drop you need.

[alanmalk]

Originally Posted by John in Santa Cruz

I wanna do something a whole lot simpler
...

In the spirit of simple and cheap (my guiding principles)...

I think a diode in the ground line of my GoPro solar controller should raise the voltage from Lead-Acid compatible to Lithium compatible.

It always can go back in the junk box if it doesn't work out as planned.

[Flyfisherdan]

Mark,

Thanks again for your reply and for answering my questions.

One more question if I may. What brand of bus bar (one with positive on one side & negative on the other) did you use?

Merry Christmas.

Dan

[Mark J]

Originally Posted by Flyfisherdan

Mark,

Thanks again for your reply and for answering my questions.

One more question if I may. What brand of bus bar (one with positive on one side & negative on the other) did you use?

Merry Christmas.

Dan

I used Blue Sea bus bars. The dual bus one is this one https://www.amazon.com/Blue-Sea-Syst...s%2C168&sr=8-5

[Brian B-P]

Originally Posted by rubicon327

I’m not sure I completely understand the need for three solar charge controllers versus one.

Separating panels with their own charge controllers allows each MPPT controller to optimize the panel voltage for maximum output of each panel, or even to allow panels are completely different operating voltages to charge the same battery. If they are identical panels in identical conditions there's no benefit, but with dissimilar panels or with varying conditions of orientation or shading (and shading is routinely different) it avoids compromising the output of one panel because of another panels different conditions. With PWM controllers there would be no such advantage.

[Mark J]

Originally Posted by rubicon327

(I’m not sure I completely understand the need for three solar charge controllers versus one. If I have any specific questions as I design a solar system I’ll PM you)

I’ll be glad to try to answer any questions when you’re ready.

Brian hit the nail on the head in his comment above. The advantage of multiple controllers in my case was that I was tying together 3 different size solar panels (4 if you count the portable panel when plugged in) running at slightly different voltages and 2 different solar aspects on the 5.0 roof (3 different aspects with the portable). With Victron hardware, three smaller controllers don’t cost much more than one big one. The extra cost mainly comes with wire and additional fuses.

Another advantage of splitting the controllers was I was able to combine the 4 small panels in series/parallel configuration to double the array voltage of that set. Mppt controllers can take advantage of that higher voltage vs the battery bank voltage to harvest more energy from the panels.

If you tie together dissimilar panels with a single controller, you would want to wire everything in parallel and the entire system will run at the voltage of the lowest rated panel in the system. So you end up throwing away some potential, but as long as the panel voltages are reasonably similar the losses can be trivial. Most would also then stick with a PWM controller like the stock Go Power one and not bother with a more expensive Victron mppt unit. But this throws away even more solar potential, as with PWM the panels are constrained to run at the voltage of the battery bank.

But a single PWM controller with panels all In parallel is by far the cheapest, simplest and easiest way to go, no argument there. And it may be plenty adequate, depending on your needs.

[rubicon327]

Originally Posted by Brian B-P

Separating panels with their own charge controllers allows each MPPT controller to optimize the panel voltage for maximum output of each panel, or even to allow panels are completely different operating voltages to charge the same battery. If they are identical panels in identical conditions there's no benefit, but with dissimilar panels or with varying conditions of orientation or shading (and shading is routinely different) it avoids compromising the output of one panel because of another panels different conditions. With PWM controllers there would be no such advantage.

Originally Posted by Mark J

I’ll be glad to try to answer any questions when you’re ready.

Brian hit the nail on the head in his comment above. The advantage of multiple controllers in my case was that I was tying together 3 different size solar panels (4 if you count the portable panel when plugged in) running at slightly different voltages and 2 different solar aspects on the 5.0 roof (3 different aspects with the portable). With Victron hardware, three smaller controllers don’t cost much more than one big one. The extra cost mainly comes with wire and additional fuses.

Another advantage of splitting the controllers was I was able to combine the 4 small panels in series/parallel configuration to double the array voltage of that set. Mppt controllers can take advantage of that higher voltage vs the battery bank voltage to harvest more energy from the panels.

If you tie together dissimilar panels with a single controller, you would want to wire everything in parallel and the entire system will run at the voltage of the lowest rated panel in the system. So you end up throwing away some potential, but as long as the panel voltages are reasonably similar the losses can be trivial. Most would also then stick with a PWM controller like the stock Go Power one and not bother with a more expensive Victron mppt unit. But this throws away even more solar potential, as with PWM the panels are constrained to run at the voltage of the battery bank.

But a single PWM controller with panels all In parallel is by far the cheapest, simplest and easiest way to go, no argument there. And it may be plenty adequate, depending on your needs.

Thank you both. This will be helpful when I get around to designing a full solar system from scratch.

Mark: What kind of panels did you use and how did you mount them? I’m researching the new Zamp Obsidian panels that are a solid framed panel but with a much lower profile than usual. Looks like they put quite a bit of thought into the development.

[John in Santa Cruz]

Originally Posted by rubicon327

Thank you both. This will be helpful when I get around to designing a full solar system from scratch.

Mark: What kind of panels did you use and how did you mount them? I’m researching the new Zamp Obsidian panels that are a solid framed panel but with a much lower profile than usual. Looks like they put quite a bit of thought into the development.

I just discovered Zamp was acquired by Dometic (as was GoPower) so both are on my sh** list.

I've got a 360W LG high efficiency panel coming Monday, then I'll have to figure out how to mount it in place of my old 160W Escape/GoPower panel. Since this is a 60 cell panel, the PV voltage is around 40V, so I've got a MPPT 100/30 here ready to begin to figure out how to install. I like what Mark did with a plywood panel under the bench, and may end up with a smaller version of that.

[rubicon327]

Originally Posted by John in Santa Cruz

I just discovered Zamp was acquired by Dometic (as was GoPower) so both are on my sh** list.

I hear you. I’m no Dometic fan but these were developed before they acquired Zamp. I don’t want to rule out an innovative, low profile panel if there are real merits. AM Solar sells them so that means something to me.

[Mark J]

Originally Posted by rubicon327

Mark: What kind of panels did you use and how did you mount them? I’m researching the new Zamp Obsidian panels that are a solid framed panel but with a much lower profile than usual. Looks like they put quite a bit of thought into the development.

I used four 45W Obsidian panels and one 90W ‘Legacy’ Zamp panel. All are performing very well. The Obsidian panels are very light and low profile on the roof—almost as invisible up there as flex panels would be.

All the panels were Zamp “B” stock (cosmetic blems) so we quite a bit cheaper than full retail price. I tested each out with a multi-meter before mounting and they all tested above the rated power specs, and the four small panels were quite similar. Although I also am no fan of Dometic, I think these are quality panels and are made in the USA. (Not inferring that the imported panels from practically every other vendor are bad, just an observation.)

I used a combination of Zamp and AM Solar mounts, all attached with VHB tape, and buried the feet in Sikaflex. No drilling. Roof wires, internal duplex cable, roof combiner box and Sika all purchased from AM Solar. The wires and mounts they sell are really good stuff.

I also fabbed some custom brackets from aluminum angle to trolly the two front panels together that are located just aft of the Escape hatch so I could crawl up there and manually angle them if we were going to be parked somewhere for awhile. Haven’t used this feature yet, but I thought of a few scenarios where it might be useful.

[rubicon327]

Originally Posted by Mark J

I used four 45W Obsidian panels and one 90W ‘Legacy’ Zamp panel. All are performing very well. The Obsidian panels are very light and low profile on the roof—almost as invisible up there as flex panels would be.

All the panels were Zamp “B” stock (cosmetic blems) so we quite a bit cheaper than full retail price. I tested each out with a multi-meter before mounting and they all tested above the rated power specs, and the four small panels were quite similar. Although I also am no fan of Dometic, I think these are quality panels and are made in the USA. (Not inferring that the imported panels from practically every other vendor are bad, just an observation.)

I used a combination of Zamp and AM Solar mounts, all attached with VHB tape, and buried the feet in Sikaflex. No drilling. Roof wires, internal duplex cable, roof combiner box and Sika all purchased from AM Solar. The wires and mounts they sell are really good stuff.

I also fabbed some custom brackets from aluminum angle to trolly the two front panels together that are located just aft of the Escape hatch so I could crawl up there and manually angle them if we were going to be parked somewhere for awhile. Haven’t used this feature yet, but I thought of a few scenarios where it might be useful.

Wow - you did exactly what my research has lead me to. I know some folks here have had good service from the flexible panels and they seem to be a good value but I really want panels with a 25 year warranty. The Obsidian panels are super sleek and output is higher than Zamp rates them. AM solar mounts and wiring are top notch. Zamp panels are pricey though. Can you share where you found the B stock (blemished) panels? Unfortunately they are sold out on the Zamp site currently. I need to take some roof measurements. With no rooftop A/C or top fridge vent I was hoping to get 400W up there but that might be wishful thinking on a 19.

[John in Santa Cruz]

if you use an MPPT solar controller, you can run a single 400W LG NeO2 or similar panel, these are around $400, and are around 76 x 40 inches or 68 x 41 depending on the specific panel, and should fit on a 19 that has no A/C. You need a MPPT controller, because these are 40V PV 10 amp panels. The higher voltage means you don't need as heavy gauge wire on the PV circuit, as its the same sorts of current as a 18V 180W panel would run.

these are heavy duty commercial panels meant for rooftop or ground mount installations, but they are rated for a very high wind load, so should be fine mounted flat on the roof a RV

[Mark J]

Originally Posted by rubicon327

Wow - you did exactly what my research has lead me to. I know some folks here have had good service from the flexible panels and they seem to be a good value but I really want panels with a 25 year warranty. The Obsidian panels are super sleek and output is higher than Zamp rates them. AM solar mounts and wiring are top notch. Zamp panels are pricey though. Can you share where you found the B stock (blemished) panels? Unfortunately they are sold out on the Zamp site currently. I need to take some roof measurements. With no rooftop A/C or top fridge vent I was hoping to get 400W up there but that might be wishful thinking on a 19.

I got the ‘B-stock’ panels directly from Zamp. I guess I got lucky—they had a bunch of sizes available last September.

I also have no A/C currently, but wanted to leave that option open for the future. And no fridge vent, so I mounted one of the little 45W panels over the ‘flat” where the fridge vent would have been. I used standard Zamp mounts for that one, so I could reverse the outboard mounts underneath the panel. Kind of hard to explain, but when you get the panel up there it makes sense. AM solar Z-Bigfoot mounts would work in that spot as well.

[rubicon327]

Originally Posted by Mark J

I got the ‘B-stock’ panels directly from Zamp. I guess I got lucky—they had a bunch of sizes available last September.

I also have no A/C currently, but wanted to leave that option open for the future. And no fridge vent, so I mounted one of the little 45W panels over the ‘flat” where the fridge vent would have been. I used standard Zamp mounts for that one, so I could reverse the outboard mounts underneath the panel. Kind of hard to explain, but when you get the panel up there it makes sense. AM solar Z-Bigfoot mounts would work in that spot as well.

Thanks. Please provide some pictures of the solar install when you get a chance! Why did you use the one 90W legacy panel versus a 100W Obsidian panel?