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"Solar ready" RVs, experiences? What inline fuses?

jameshowison

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Jul 30, 2021
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Quite a few RVs are now advertised as "Solar Ready". We have an rPod from Forest River. Ours is not the Zamp SAE connector stuff, but a GoPower branded thing (well, that's what's on the sticker at least)

What this means for the rPod is that there is a through-the-roof gland that (I think) takes MC4 connectors. Those are attached to two 10AWG cables (red/black) that run into a cabinet, and loops back out and directly to the battery. The cabinet has a sticker on it showing where the solar charge controller should go. I gather the idea is that you cut the cable at the loop, then place the SCC inline. I guess using a continuity checker to know which part of the loop is going to the battery and which to the panels, or I guess just see which end has the 12v across them from the battery? :)

Of course the actual path the cable takes is hard to know, and there is a ton of foam disguising spots where the cable goes in and out.

Nonetheless, I think I can (temporarily) use this wire. One question, though: there doesn't appear to be a fuse anywhere. I think there should be a fuse at the battery, no? But there doesn't seem to be one there at the moment.

Ok, explored a bit further, the sticker is "GoPower" and they do actually have an installation guide here. Indeed their kit provides an in-line fuse "as close to the battery as possible", cutting the wire and adding that. https://gpelectric.com/wired-for-solar/ with a drawing of what was actually installed (I have the roof gland preinstall) and installation details on p 16. https://s3-us-west-2.amazonaws.com/catsy.549/56587_MANUAL_GP_RV-KITS-SYSTEMS.pdf

So I have a Victron MPPT I'm not currently using and will install that temporarily. Any suggestions for the fuse? Options seem to be using an MBRF fuse at the battery terminal (but that's a few extra dollars) or the line blade fuse and holder (are those weather proof)?

 
Should have a fuse between the controller and the battery. Close to the battery.

No fuse needed on the "solar ready" wire connecting the panels to the controller.
 
Have fun with that. Also you should look up here some threads on disabling the onboard converter if you’re running an inverter to feed the RV outlets. Otherwise you’ll just be making a battery go dead all the time
 
Breakers are always better than fuses where practical. On a system as small as yours I would have one between the panels and charger and one at the battery as well. If nothing else it makes isolating either side a snap.
 
Breakers are always better than fuses where practical.
I’m not sure about that

The right fuse I think is better in a lot of small solar applications. Often a lot less money. A well designed system shouldn’t have “nuisance trips” and a fuse is usually a tiny bit delayed so it shouldn’t ever blow unless it needs to. My opinion anyway.
 
So, something like the Blue Seas systems 285 series?


I'm using the 187 series of breaker between my Victron 100/50 MPPT and the positive common bus bar. The mounting studs on the 187 worked better for my situation than on the 285 series. I bought mine through BayMarineSupply.com. I used the 70 amp breakers. 60 would have been better, but at the time they were out of stock.
 
Follow up to this thread. All went well, I used the batter terminal MBRF fuse (easier for me to mount).

Later, though, I found that the solar cable did already have a fuse, one of the thermal auto reset ones. It was buried in foam.

Worse, though, when I removed the MC4 entry gland from the roof (ended up moving it) I found that the solar ready cables had a pigtail of better cable from the MC4 connectors, but the connection had a failed crimp, the positive just fell out. Typical. This was buried in the roof, so impossible to check without taking the entry gland off.
 
Sigh, I have found more bad connections than I care to find. I finally had to turn my 120v 60a Lithium battery charger on, and I'm getting a whopping 25a out of it. Something is wrong somewhere. Most everything is being replaced with my upgrades, so hopefully that whole circuit will be disabled.
 
Sigh, I have found more bad connections than I care to find. I finally had to turn my 120v 60a Lithium battery charger on, and I'm getting a whopping 25a out of it. Something is wrong somewhere. Most everything is being replaced with my upgrades, so hopefully that whole circuit will be disabled.

If this is a typical converter, programmed for LiFePO4 charge profiles, it may not be surprising at all that you're not seeing 60 amps of charge. Many of the common names in converters just don't produce like we want them to.
 
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