House solar panel on 4x4 roof (Pt 2)

Hello again Lyndon: my take on this subject is that the Anderson plug is the weak link if it is outside in the weather, there are several different adaptions for keeping moisture out of the cables but none of them will keep all the moisture out and the cables will corrode in time "IMO" and experience. NOTE.. I am not an EXPERT in this field .
On my setup I have the cables all fully sealed till they get inside the vehicle.

It will be interesting to hear from the people with vast knowledge in this field .

The solar panels will come with pre-fitted MC4 connectors. I kept these, and bought MC4 connectors for my wiring, but I was able to borrow a crimping tool. I haven't used or seen the tool-less type, so can't comment on those.
What are you connecting to at the other end? Does it have an Anderson plug already? I wired mine into a DC-DC/MPPT charger, via an isolator, so no Anderson plugs involved. I found it better to buy solar figure 8 cable by the metre, and crimp the MC4 connectors at the solar panel end (but again, I had free access to a crimping tool).

I'm sure you've done your research. You'll need an MPPT charger that can handle the 40V+ coming from the panels. I used an Enerdrive one, but partly because it also supported the 24V input from my alternator on the DC-DC input, along with the higher solar voltage.

G'day Lydon.
I see you and others CRIMP the MC4's, ok, but since I sometimes have to reconfigure things/ always fiddling, I have soldered the wires into MC4's and only folded over ears on outers. This is as others mentioned, to exclude the moisture. I have TWO systems running house panels on my shed and both run at around 68v. over 15 metres. Having MC4 connected panels x3 on my Ute but at 20v with Triple Y connectors.
Yours at 40 v approx, you may not need to upgrade the wire size from the 12 v system because the current although more , the doubled voltage will transfer the ENERGY quite well, IMHO! DO a Preliminary check to see MAX amps on the chosen MPPT to see. Some voltage drop will be there, but is it more significant than the system on 12v with a HIGH current being passed? Only then would I consider cable upgrade!
Ps if soldering, pre tin all connectors required in the wire ports and tin wires too. Then on assembly only a small heat and a touch of solder is required for a SECURE joint! It allows for any repair or alteration when not at home. I cannot uncrimp things then!

I never crimp Anderson plugs either!

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Hi Lyndon,
The Sprinter's four panels came with short leads and MC4 connectors so I removed the leads and connected my cable directly into the junction boxes on the panel. To avoid making inter-connections on the roof I brought the four separate cables down to my electrical cabinet and performed the series/parallel terminations there. Apart from practical wiring considerations it allows me to easily assess individual panel performance if the need should arise.
MC4 connectors seem to have reliability but exposed Andersons not only allow water ingress to the contacts but also to the cable ends where it will travel inside the cable for a short distance and induce corrosion.
For reliability I minimise terminations everywhere I can as, even if performed well, they are a potential for problems.

I used adhesive tape to mount my panels, I used to plug connections to make the installation easier and needed to ensure the connections would be reliable as no access to them without removing a panel.

I decided to use gold plated EC connectors as they are a compact and reliable. In my case mini EC 2 connectors were more than adequate. I used adhesive heat shrink to seal the connectors and cable never had a problem with them.