Any good reasons not to ditch the MC4 connectors?

[swduncan]

So my solar system consists of four 50 watt flex panels and a Victron 75/10 controller. I will change if the panels are in series or parallel depending on conditions, and I’m getting tired of the bulky and hard to disconnect MC4 connectors on the panels.

I use the Anderson Powerpole connectors for everything else, but haven’t swapped the MC4 connectors for them yet.

Anyone else made the switch & have regrets?

Thanks!

 

[luthj]

You could wire up a DPDT switch to change between 4s to 2p2s configuration. This would eliminate the need to plug/unplug. I agree, MC4 connects are not designed for repeat plug/unplug, so its super annoying, and will probably wear out the connectors quickly.

The anderson connectors are generally a good choice. If they are exposed to the elements, you may want a dust proof boot. An occasional application of dielectric grease isn't a bad idea, but the connectors should be self wiping, so they will stay clean on their own generally.

It will add a bit of resistance (probably not a problem with the currents you are dealing with), but you could leave the MC4 connectors alone, and just make an adapter.

Make sure your anderson terminals are sealed to the insulation with adhesive heat shrink or similar. As water will wick up the wire under the insulation given enough time. Bad mojo.

 

[john61ct]

If warranty is a concern, make up APP-MC4 adapters

 

[WOODY2]

I swapped mine over to SAE type connectors.

 

[john61ct]

OK for low amps, but check for corrosion every once in a while

 

[craig333]

First thing I did was cut mine off. Like the chinese would honor the warranty anyway.

 

[luthj]

I have purchased panels from US suppliers. (They may have been assembled in china). When several of the panels developed stress cracks in the cells after 2 years, they replaced the panels free of charge (including shipping).

Now, flexible panels usually have a much shorter warranty period, so read the fine print (they just don't last as long).

 

[Rando]

Ditching the MC4's is a great idea, as others have pointed out they are not the right connector for this application where they are plugged/unplugged on a regular basis. However, I wouldn't use Anderson Power Poles, these aren't the right connector for this application either. Instead I would suggest either Weatherpack or Metripack connectors. These are rated for wet outdoor environments, are latching and have strain-relief for the cable.

As an aside, I am not sure why APP are so popular, objectively speaking they are a pretty crappy connector, which is why you almost never see them used in a professional application.

 

[john61ct]

Amphenol-Deutsch even better than weatherpack.

https://laddinc.com/products/connector-selector/

But I'm happy with APP, 10A up to 350A.

Once you've chosen, best to standardize everything on that, payback the investment in supplies, crimpers etc

 

[luthj]

Amphenol stuff is quite good, especially in severe environments. APP is good, especially for high current applications that will see frequent connect/disconnect. For items that will rarely get disconnected, and are exposed to the elements the APP connectors can develop corrosion or high resistance.

The durability and ease of assembly are big pluses for APP. It is very expensive to locate 200A plus connectors that can tolerate regular disconnect (obviously not applicable to solar panels).

As for professional applications, pretty much the standard for electric fork truck battery connections is APP, as well as data centers with DC main buses.

For lower current applications the APP have a good range of quality alternatives though.

 

[DaveInDenver]

As an aside, I am not sure why APP are so popular, objectively speaking they are a pretty crappy connector, which is why you almost never see them used in a professional application.

I adopted them because of amateur radio and involvement with ARES. For whatever reason the emergency response groups with in ham radio standardized on them. I wouldn't call them the worst connector ever designed but sure, there are better. For example the earlier suggestion of a Weatherpack or Metripack as an improvement for vehicle applications. But I put Powerpoles on my PV panels because of the lowest common denominator aspect for all my sub-40 A 12 V power so I can run any source with any load, radios, fridges, supplies, panels, controllers, etc. If I never intended to plug into another ham's power then I might have gone a different way but it is what it is.

 

[Hillbilly Heaven]

APP connectors are very popular in material handling equipment like electric forklifts or in large battery banks. They make for easy no tools battery changes. When you run forklifts and mobile robots 24/7 they are needed so operators can do battery swaps without an electrician. APP connectors like someone has mentioned are designed for frequent connect and disconnect. This is the way the contacts remain clean. They are designed to be self cleaning. If left connected two things happen. The contact develops an oxidized film and also the spring tension is weakened.

If the contacts that are used are silver plated then any oxidation that occurs is silver oxide which in itself is conductive. I will take silver any day over tin or gold.

 

[DaveInDenver]

FWIW, Powerpoles come in tin plated and silver plated terminals. The tin plated ones are rated for 1,500 cycles and the silver 10,000, which is because tin will experience galling when used in a contact that slides so the self-cleaning action is offset by that.

Also if you intend to leave the connection in place long term you can coat the terminal surfaces (easier done before you put the terminal in the contact body) with dielectric grease to reduce the corrosion.

 

[Rando]

Amphenol stuff is quite good, especially in severe environments. APP is good, especially for high current applications that will see frequent connect/disconnect. For items that will rarely get disconnected, and are exposed to the elements the APP connectors can develop corrosion or high resistance.

The durability and ease of assembly are big pluses for APP. It is very expensive to locate 200A plus connectors that can tolerate regular disconnect (obviously not applicable to solar panels).

As for professional applications, pretty much the standard for electric fork truck battery connections is APP, as well as data centers with DC main buses.

For lower current applications the APP have a good range of quality alternatives though.

Agreed on the Anderson SB connectors being used for high current applications, but the 15 - 45A Powerpoles discussed here are seldom used outside hobbyists. I can see using them if you are a ham radio buff who shares gear with others (where they are unfortunately the standard), but starting from scratch, there are much better ways to go including all the suggestions here.

 

[DaveInDenver]

Agreed on the Anderson SB connectors being used for high current applications, but the 15 - 45A Powerpoles discussed here are seldom used outside hobbyists. I can see using them if you are a ham radio buff who shares gear with others (where they are unfortunately the standard), but starting from scratch, there are much better ways to go including all the suggestions here.

A couple of professional uses (e.g. not ham and model railroads) that I'm aware of is APC uses SBS for their batteries and I've seen the PP15-45 type used on data center backplanes (where it's integrated into housings and called the Power Pak).