18 replies to this topic

[Cbessler]

Hey everyone! Just finished my solar install and wanted to ask a few questions and I guess double check my system against the experts. I have a 2014 fwc fleet. Looking to make sure everything here is appropriate and won't be a fire hazard etc with the pre-installed 12g wiring.

I added 350w of renogy flexible solar panels wired in series to the roof for lithium and the smaller wiring. I have a 206ah sok lithium battery I charge to 14.4v and a 100/30 victron mppt solar charge controller.

The panels come into the 12g sae roof connection mounted with 10g mc4 connectors and a sae adaptor for the reversed polarity issue fwc has. It then runs on the stock 12g wiring to the charge controller and 10g wiring from the storage cabinet through a predrilled hole into the battery. The 10g is roughly just a couple of feet. I spliced the wiring found from the pump cabinet area and just left the old wiring "dead" that runs into the battery compartment. Nothing fit there for the install so had to come up with something else.

I added a 40amp breaker (let me know if you guys think 30 amps is better here) and then another before the battery (again at 40 amps).

I have found a few forums on here regarding the amp rating and length of wire for the pre-installed 12g wiring. Does my system seem ok here? I don't want a fire hazard etc.

Here are some panel specs:

Maximum Power at STC: 175W
Module Efficiency: 17.3%
Optimum Operating Voltage (Vmp): 19.5V Open-Circuit Voltage (Voc): 23.9V
Optimum Operating Current (Imp): 8.89A Short-Circuit Current (Isc): 9.50 A
Operating Temperature: -40°F to 185°F (-40ºC to +85ºC)
Maximum Series Fuse Rating: 15A

Attached Files

•  20220503_143931.jpg   173.67K   51 downloads

[Cbessler]

Here is the roof setup. I've cleaned up some other wiring haha

Attached Files

•  20220503_193519.jpg   150.72K   62 downloads

[m5040]

If the specs you listed state 15 amp fuse max, wouldn't at 10 amp be more realistic?  And 30 or 40 amp is out of the ballpark

[Cbessler]

So should I switch the breakers to more like 20 amps coming in and a 30 beneathe? I think that is per panel specs.

[camper rich]

Are you sure you want your panels wired in series?  I'm thinking parallel.  Series will add up the voltage of all the panels, parallel adds up the amps.

[Cbessler]

I've read adding up the panels in series will allow for better volt creation for the lithium for charge efficiency percentage correct? I've also watched videos on in parallel charging and only one cell needed to kick the whole panel out. I chose in series because the higher volts for lithium. I did set it up so that I could change it over if I wanted to tho

Edited by Cbessler, 06 May 2022 - 02:24 AM.

[Vic Harder]

This looks good, except the breaker size is too big. Series is what I would do. More volts is better, the MPPT will have more room to work with and create the AMPS camper Rich is talking about.

[Cbessler]

Totally and thanks vic for the info! Always appreciate you on these threads! I've come across a ton of stuff and wanted to make sure mine was good. Drop it to a 30 amp breaker then?

[Vic Harder]

Totally and thanks vic for the info! Always appreciate you on these threads! I've come across a ton of stuff and wanted to make sure mine was good. Drop it to a 30 amp breaker then?

The manufacturer says 15A max. Your panels are rated at less than 10A short circuit current, and in series that is not additive, so 10-15A would be right.

Unless you are fusing on the output side of the MPPT? That should be super close to the batteries, and a fuse would be overkill there.

[Cbessler]

Hey vic thanks for the info. I will update the first breaker prior to mppt to 15 amps. Is that where it should be? Between the panels and the mppt charger?

Ohhhh or should I fuse the actual panels on the roof?

Renogy 15A Male and Female Connector Waterproof in-Line Fuse Holder w/Fuse, Black https://www.amazon.c...1KB3NKDM9?psc=1

Then maybe just keep the 2nd breaker after the mppt. The other breaker is mainly there as a way to service the system and looks like I built it too big. It's nice switching things off and on too. Yes it's really close to the batteries maybe 1.5 ft ish

Edited by Cbessler, 07 May 2022 - 05:09 AM.