I stumbled upon these “MC4” connector for roof solar panels. Supposedly rated for 30A and IP68. I guess they are fine at more then double current. Same diameter as 4mm bullet/banana so inserts might just be directly swappable (at least male is just to click in).
Dirt cheap at 3 EUR per pair in my country.
I will play around with these as phase conectors, lets see how they like 60A 
Did you try it ? 
Those connectors are not supposed to be disconnected regularly.
The quality connectors from Stäubli are rated only for 100 connection cycles.
They are also really bulky and the cheap ones I used in the past for solar connections were also prone to corrosion.
Not yet, have at least a few months before my build is running in water.
I did however see another MC4 connector that was marginally larger plastic casing and cost around an EUR more per pair. Rated for 50A continuous.
I will be using the ones I bought for phase connections. I will keep an eye on them.
Yeah, I think that is not a problem… It is more then needed.
I absolutely do not agree. Significantly smaller then quite some alternatives. Image shows next to 4mm bullet.
The ones I bought are very pure copper and tinned, don’t see why they would corrode more then other non gold plated connectors. But then we are at way more expensive connectors if you want proper gold plating.
