A Question on MPPT Controllers

[highwaypirate]

I got a feeling this post might get me some backlash, but I don't know where else to ask.

I had recently ordered a Victron 100/20 but had extreme difficulty getting it wired up. The terminal ports on the underneath, regardless of how tight the cables are, always move around and eventually pop out. Now I've been using a rebranded PWM controller for years (and its still in use), but a few here had roasted a previous post I made where I stated the fact I'd prefer staying with PWM over MPPT for their simplicity, despite not being as efficient. I have attached two photos of the 100/20 and the PWM side-by-side; my question is are there any MPPT controllers that use screw/bot terminals? The ones which Victron (and some Renogy ones) use are giving me great safety concerns.

Thanks!

 

[Brucey]

You need to use fine stranded cable on those Victron SCC terminals.

 

[seneysolar]

I cant think of any CC with screw terminals like that.

Yes, victron specs a high strand count wire so it will form to the connector port.

Honestly i have not had that issue with mine and I ran 7 strand pv cable into my 100/30. (Not recommended by victron)

I give all wires a "tug" on occasion, the ones i find loose are on my PV/DC breakers from Midnight, those need occasional tightening.

 

[BentleyJ]

Have you tried using ferrules?

 

[highwaypirate]

I know, when I first saw these CanadaProof ones I thought the terminals were odd. But they've been super reliable and barely come loose (one might give a slight wiggle after a year of hard roads). I haven't seen any MPPT using connections like those ones, though wouldn't it make more sense to use them? If a screw gets stripped, just replace with another one instead of buying a CC. There has to be atleast one company that used screws similar, though I could be looking for something that may not exist.

I had a Renogy with the same terminals as the Victron, but the strands broke apart within and shorted the CC to a crisp. That's my safety concern. If my install was in a non-moving environment (a house), I'd feel a little safer with them.

 

[Q-Dog]

The mistake I see most with the Victron SCC is folks not checking that the screw terminals are unscrewed all the way before trying to insert the wire. Watch the wire openings as you unscrew the terminals and you will quickly understand how the wire clamps work.

And before you insert the wires you need to make sure the strands are very smooth and neat, not frayed on the ends.

 

[highwaypirate]

Have you tried using ferrules?

I have actually, but I always ended up with the wires not being tight/popping out.

 

[Q-Dog]

Have you tried using ferrules?

Do not use ferrules on the Victron MPPT.

 

[Zwy]

Use fine stranded wire with a crimped ferrule. You can't get any better than that.

 

[Zwy]

Do not use ferrules on the Victron MPPT.

I was unaware. Why is this so? Curious.

 

[BentleyJ]

I have actually, but I always ended up with the wires not being tight/popping out.

Don't have an explanation. If the ferrule is crimped properly and the screw terminal tightened down properly, should be a reliable connection. Is this a high vibration environment?

 

[Q-Dog]

I was unaware. Why is this so? Curious.

It seems we keep having this discussion. It has to do with the way the wire clamps around the wire strands.

Is high strand a Victron only thing? Calling sunshine.

Yeah. To my knowledge it's primarily an issue with the new MP-II AC terminals. I did watch a YouTube video where Victron DID honor warranty and I think the guy used ferrules. Personally I used nm12/2 wiring on the ac side of my mp-ll (and it’s a new model). So I am ordering an “IMO” type dc...

diysolarforum.com

 

[BentleyJ]

Do not use ferrules on the Victron MPPT.

Looks like a typical Phoenix Connector screw terminal, should be compatible with ferrules??

 

[highwaypirate]

Don't have an explanation. If the ferrule is crimped properly and the screw terminal tightened down properly, should be a reliable connection. Is this a high vibration environment?

Yes. It's for an SUV that frequents rough roads and fields (I supply power for remote workers).

 

[Brucey]

Looks like a typical Phoenix Connector screw terminal, should be compatible with ferrules??

Victron specifically recommends against use of ferrules in the SCCs. Now on their inverters they do recommend them.

 

[Zwy]

It seems we keep having this discussion. It has to do with the way the wire clamps around the wire strands.

Is high strand a Victron only thing? Calling sunshine.

Yeah. To my knowledge it's primarily an issue with the new MP-II AC terminals. I did watch a YouTube video where Victron DID honor warranty and I think the guy used ferrules. Personally I used nm12/2 wiring on the ac side of my mp-ll (and it’s a new model). So I am ordering an “IMO” type dc...

diysolarforum.com

And then you have this post which is from the manuals. https://diysolarforum.com/threads/source-to-buy-quality-wire-ferrules.60670/post-750872

After using ferrules, it would be rare I'd go commando.

 

[Zwy]

Yes. It's for an SUV that frequents rough roads and fields (I supply power for remote workers).

What you have been doing doesn't seem to be working.

Your call on whether to use a ferrule.

 

[Q-Dog]

And then you have this post which is from the manuals. https://diysolarforum.com/threads/source-to-buy-quality-wire-ferrules.60670/post-750872

After using ferrules, it would be rare I'd go commando.

That has nothing to do with the SCCs. Do not use ferrules in the Victron Solar Charge Controllers. They don't use the same connectors as the inverters.

 

[zanydroid]

Add a strain relief clamp on those conductors? That will reduce the amount of momentum they can pick up while bouncing around

 

[highwaypirate]

I saw a video from Projects in Paradise 808 where he mentions he uses ferrules on his Victrons, but I've heard from both sides of their use.

My coworker suggests I modify the Victron by frankenstein-ing it to somehow use different terminal types, but I'm not a mad scientist and wouldn't know where to begin. I'll keep tinkering with the Victron, but as far as my setup goes I'm quite contempt with my cheap PWMs for now.