Quick Thought on Cable Sizing for Victron Controllers

[Deleted member 91418]

While at work, I had a strange thought come to mind...

I had a Victron 100/20 that didn't work out well before, as some may remember. It was due to the terminals they use and why they wouldn't hold cables down. Since then I've seen some other Victrons which require 6AWG cables, however, I've never heard of such MC4 or PV wiring that large. My question is... how do you get your PV wires (most are 10AWG) into the Victron and not have them fall out? I was having a brain-spasm and thought:

...if one array was brought down to it's own + and - busbar where it then attached to 6AWG cables, going into the Victron, would that work?

Let me know what you guys think! I personally won't try it, but the concept has been nagging my attention.

I still believe screws with washers are a much better connection method than what (nearly) all MPPT's use.

 

[bolhuijo]

It is easily done with most combiner boxes:

Attach your array(s) to the inputs and run 6AWG cables from the breaker/shutoff to the MPPT input.

 

[sunshine_eggo]

You never answered the question in the other. Was fine strand wire in accordance with the manual used?

I have a 250/100 and a 100/30, and I had a 150/100. I use extremely fine strand wire, and I've never had a connection issue. However, I have decent upper body strength, and I can get them very tight. My wife as the "torso of a chicken carcass picked clean of meat" - her words, not mine - intended to convey her lack of upper body strength. She could not tighten these adequately.

Ring terminals also involve crimps, which have their own issues.

I don't get how the bus bar is somehow a better option. If you can't get the terminals tight enough, you can't get them tight enough.

 

[seneysolar]

I believe the thought is for transitioning to the proper wire before going to the CC.

Transition from say 7 strand PV wire to a high strand wire as called out by Victron?

The answer is yes, but I do it with a breaker box instead of a bus bar, same idea. I run the PV wire to the breaker then high strand to the controller. Ultimately, I just purchase high strand PV wire now as I like working with it.

 

[cs1234]

Seems like it would be hard for the cables to come loose when you have everything as tied down as @seneysolar does in this picture above.

 

[Deleted member 91418]

I did convert my systems wires to marine grade fine-strand wire earlier, but still to no avail. Also, if precision screw drivers were able to break Victron's terminal screws, imagine what upper body strength would do. So far after 4 years on my SCC, my terminal crimps haven't let loose yet.

The answer is yes, but I do it with a breaker box instead of a bus bar, same idea. I run the PV wire to the breaker then high strand to the controller. Ultimately, I just purchase high strand PV wire now as I like working with it.

This is also another good idea to try out! I did find some distribution block bus bars (two bolts) on China-Zon that I'd be willing to experiment first. But even if it does work, the Victron will never be put into permanent production on my systems.

That combiner box does make things a LOT simpler; also like how it has MC4 inputs already. If the trunk of my SUV was large enough I would go for one of those.

Seems like it would be hard for the cables to come loose when you have everything as tied down as @seneysolar does in this picture above.

I agree. For a normal application where there is plenty of room for that board, I would do something very close to his setup. But since I live out of a small SUV my space is super limited.


This is what my boss's wife had built out of the old 100/20; she added a couple pieces of wood to keep the wires from moving about. Even though this worked flawlessly (they were held down good), the terminals themselves still wouldn't tighten down enough. It was almost as if the screws would 'pop' when it was fully tightened, but not enough grab was there. Hence why I would like to try using slightly larger wire and see if the connecion could be better. Again... the Victron will never be used in the permanent installation, but more for testing.

 

[JRH]

Seems like it would be hard for the cables to come loose when you have everything as tied down as @seneysolar does in this picture above.

That’s part of the reason on boats and RVs etc…. we tie them down snug and close ..the other reason it prevents chafe… if I can I find a wire that is easily moved ….I’m securing it to somthing.

 

[Deleted member 91418]

An update on the Victron: we finally got it working today with 8AWG wires and began charging with a single 50w panel. However, during our solar testing my boss noticed a burning odour coming from the Honda. The Victron's terminals were melting.

After a lot of diagnosing, we were unable to find the cause of the burning. My boss (a long-time user and fan of Victron) had reached out to the company as to why it's terminals differ from an older 100/20 from 2022. As far as I'm concerned, I will not be using anymore Victron products in future builds. I know they are a good product and they have lots of potential to offer, but I got a bad gut feeling about this; and the most important rule in my life is to always go with your gut feeling. Sorry it didn't work out.

 

[seneysolar]

An update on the Victron: we finally got it working today with 8AWG wires and began charging with a single 50w panel. However, during our solar testing my boss noticed a burning odour coming from the Honda. The Victron's terminals were melting.

After a lot of diagnosing, we were unable to find the cause of the burning. My boss (a long-time user and fan of Victron) had reached out to the company as to why it's terminals differ from an older 100/20 from 2022. As far as I'm concerned, I will not be using anymore Victron products in future builds. I know they are a good product and they have lots of potential to offer, but I got a bad gut feeling about this; and the most important rule in my life is to always go with your gut feeling. Sorry it didn't work out.

Wow! with only a 50w panel there surely couldn't be that much current flow?

Given the history of that controller, id suspect the terminal is cracked loose inside from the board.

If its not under warranty id cut that thing open and have a look.

 

[Deleted member 91418]

If its not under warranty id cut that thing open and have a look.

Victron had refused to cover the warranty back in March because it was sold by a private seller on Amazon. But with how badly the case is melted, I don't think it would be very hard to open it lol.

But I can't blame Victron completely; every MPPT it would seem uses the same connectors, which in our opinion is not good enough for my application (mobile). Until a company changes to something similar to what my PWM uses, I'm afraid I cannot join the MPPT band wagon for a long time yet.

 

[Deleted member 91418]

We're just surprised no one else had mentioned any complaints or issues regarding this method of attaching wires. You would think someone had faced some sort of difficulty? My boss has been working with Victron controllers for years, and never found terminals as bad as that 100/20. I also haven't heard Will say anything bad about them. But because my boss has helped in, I can disregard 'user error' as a reason for its failure. And how many other Victrons might have the same issue? Scary.

 

[Bluedog225]

I don’t like them myself. But they seem to work well.

Maybe you got a bad unit. Maybe it’s damaged. Maybe you’re doing it wrong.

The extraordinarily large user base for Victron MPPTs seems to generate very few dissatisfied customers. In fact, I don’t recall any.

I don’t think you’re going to get much traction talking down Victron quality.

Another way to approach this is to learn the lesson that you should’ve bought from a reputable Victron dealer. We can give you some options in that regard if you are interested.

All the best.

 

[seneysolar]

A bit off track but have you looked at these? It appears that the wires are permanently molded into the case. Your bus bar transition idea could work here with crimped ring terminals.
Epever waterproof

 

[Brucey]

I don’t like them myself. But they seem to work well.

Maybe you got a bad unit. Maybe it’s damaged. Maybe you’re doing it wrong.

The extraordinarily large user base for Victron MPPTs seems to generate very few dissatisfied customers. In fact, I don’t recall any.

I don’t think you’re going to get much traction talking down Victron quality.

Another way to approach this is to learn the lesson that you should’ve bought from a reputable Victron dealer. We can give you some options in that regard if you are interested.

All the best.

Current Connected, Pike, inverter r Us all solid options.

 

[Deleted member 91418]

A bit off track but have you looked at these? It appears that the wires are permanently molded into the case. Your bus bar transition idea could work here with crimped ring terminals.
Epever waterproof

I wish I could... but my LiFePO4 can't charge over 14.0v, otherwise the BMS sky-rockets to 16v and higher. I don't see a way of changing settings on that device.

If it was just me doing this charge controller event, I would gladly accept 'user error' as an answer. But because my boss has 32 years in solar installs and uses nothing but Victrons for work, I can't accept that.

 

[seneysolar]

I wish I could... but my LiFePO4 can't charge over 14.0v, otherwise the BMS sky-rockets to 16v and higher. I don't see a way of changing settings on that device.

The Epever charge controllers need the remote for programming.

MT50 Remote

 

[featherlite]

She could not tighten these adequately.

The manual for my Victron 100/50 MPPT says torque all four terminal screws at 1.6 Nm = 14.16 in lb.
I would think that any garden variety sissy could muster up that amount of torque.

 

[Deleted member 91418]

Unfollowing thread. Thanks for showing us all how much of a dick you are.

 

[Checkthisout]

Pirate, if the terminals on the far right are where the PV wires connect, you're not opening the terminals all the way up before inserting the wires.

To open them properly, you need to apply some downward pressure on the screw and then turn it counterclockwise until you can visually see/feel the clamp all the way open.

Otherwise you end up putting the wire behind the clamp or a mix of behind and in front with only a couple of strands getting clamped.

Not my best labeling job but left to right.

Closed. Closed. Partially Open. Open (Partially) Open (Partially) and Im not sure.

The question mark one looks fully open.

If you look at the two on the left, those are Closed and clamped tight. You can see they will clamp even the thinnest gauge wire but you can see how if you're not careful about the clamp position when you go to insert the wire, you can get some strands behind the the clamp.

If you look at the one labeled "po" you can see how if a wire gets put in there and the clamp gets tightened, some strands will be behind the clamp and some in front leading to a poor/loose connection.

 

[KnobCountry]

On my 100/20 I used anchor 10awg marine grade wire and 10awg crimp ends that I crimped until they could slide into the terminals.

https://m.media-amazon.com/images/I/31gZeU6DnlS._SS142_.jpg

While tightening the terminal down it felt much more secure than the bare wire alone.

I also used the optional wire clamp that victron should include with these to further lock it down.

https://m.media-amazon.com/images/I/71e5nmAuX5L._AC_UF894,1000_QL80_FMwebp_.jpg

 

[Checkthisout]

And to add, if you shove the wires into the closed clamp and then turn the screw counterclockwise (loosen) the wire will actually get clamped in there loosely, the screw will even tighten but the connection is improper and very poor and the wire will just pull out.

 

[cr117]

No issues with my Victron MPPT using 10AWG and 14AWG wires. Terminals have been holding securely without anything coming loose. This is in a power station that I throw in the back of my 4x4 and bounce all over the place.

 

[sunshine_eggo]

Unfollowing thread. Thanks for showing us all how much of a dick you are.

Oh my.

 

[seneysolar]

Oh my.

Deleted profile too

 

[Daddy Tanuki]

Unfollowing thread. Thanks for showing us all how much of a dick you are.

being that he was making fun of @sunshine_eggo and his wife you are looking for a reason to be offended. mission accomplished. My Lord and I thought the sissy boys on the chainsaw forums were thin skinned.