House solar panel on 4x4 roof (Pt 2)
Submitted: Wednesday, Feb 25, 2026 at 12:34
ThreadID: 152215
Views:1134
Replies:6
FollowUps:5
Member - lyndon NT
Hi All
Thanks for the feedback the other week.
Just wondering what type of connectors to use. I have the skills and
tools to crimp Anderson plugs. Have a pack of various plugs and lug sizes I keep for spares.
Or should I keep the MC4 type 4 connectors on the panel and use those type, with Anderson on the other end. I don't have Crimpers for the MC4 type,though I believe they are available now in a tool-less variant.
No sure if I can buy those individually at the wholesalers. Then there could be the issue of different types of MC4 (not sure if the tool-less variant) is compatible with what will come on the panel. Probably a 460w or there about Canadian solar panel, think I can pick these up for not much more than $200
Or I could just purchase one of
THESE
Though cable size is on the light size, they do a 5m one, but even that probably isn't quite long enough with the Troopy and where I need to run it.
So what's the general consensus, hack it off and install an Anderson plug?
Cheers
Lyndon
Reply By: Member - nick boab - Wednesday, Feb 25, 2026 at 14:09
Wednesday, Feb 25, 2026 at 14:09
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 .
AnswerID:
648977
Follow Up By: Member - lyndon NT - Tuesday, Mar 03, 2026 at 09:39
Tuesday, Mar 03, 2026 at 09:39
Hi Nick
Less
water and
debris ingress is always better, that said, the 175A Anderson plug under the rear of the car has been there for over 20 years and still functions.
Cheers
Lyndon
FollowupID:
930636
Reply By: Doc - Wednesday, Feb 25, 2026 at 14:25
Wednesday, Feb 25, 2026 at 14:25
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.
AnswerID:
648979
Follow Up By: Member - lyndon NT - Tuesday, Mar 03, 2026 at 09:50
Tuesday, Mar 03, 2026 at 09:50
Hi Doc
I have one the 50A version of one of
THESE
Anderson plug on front of car,(see photo's below) this also splits inside the vehicle, Anderson to Anderson in case I wanted to put a supply though the side window. Povo set up until a full rewire,which who knows when that will ever be.
Thinking I might see if I can get the tool-less MC4 connectors, make a short lead to Anderson, then just put a patch lead in between. That way I can use the patch lead (Anderson to Anderson)for other purposes.
Cheers
Lyndon
FollowupID:
930637
Reply By: RMD - Wednesday, Feb 25, 2026 at 17:15
Wednesday, Feb 25, 2026 at 17:15
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!
AnswerID:
648980
Follow Up By: Member - lyndon NT - Tuesday, Mar 03, 2026 at 09:55
Tuesday, Mar 03, 2026 at 09:55
Hi RMD
Thanks for your input, I'm a rusted on crimping type of guy :-)
Yes, the higher voltage will go a long way to mitigating Vd.
Going to see if I can't get a couple of Tool-less MC4 connectors.
I think I'm pretty good with the MPPT, slight overkill like most things I usually do.
Cheers
Lyndon
FollowupID:
930638
Reply By: Allan B (Sunshine Coast) - Wednesday, Feb 25, 2026 at 19:40
Wednesday, Feb 25, 2026 at 19:40
.
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.
AnswerID:
648981
Follow Up By: Member - lyndon NT - Tuesday, Mar 03, 2026 at 11:32
Tuesday, Mar 03, 2026 at 11:32
Hi Allan
Thanks for the input. It is indeed a POVO job I'm doing here. Connections will be tucked up under the panel, except for the Anderson plug on the Bull Bar. It's just for plugging in when stationary for a while.
Hoping to do some overnight hikes, body permitting...
Sprinter eh,
well, some of us are still enjoying the "comforts" of the Troopy :-)
Cheers
Lyndon
FollowupID:
930639
Follow Up By: Allan B (Sunshine Coast) - Tuesday, Mar 03, 2026 at 11:40
Tuesday, Mar 03, 2026 at 11:40
…….."still enjoying the "comforts" of the Troopy"
I wish.
FollowupID:
930640
Reply By: Member - LeighW - Thursday, Feb 26, 2026 at 12:32
Thursday, Feb 26, 2026 at 12:32
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.
AnswerID:
648982
Reply By: Member - lyndon NT - Tuesday, Mar 03, 2026 at 09:36
Tuesday, Mar 03, 2026 at 09:36
Probably should have posted these first. Input on Bull Bar.
Most likely only be plugged in when stationary.
I know, not ideal. But for the week or two this gets used for from time to time, it will be fine.
Panel connections up top will be under the panel itself.
Cheers

Anderson plug

Anderson plug 2
AnswerID:
648988