Beware of the APEXIUM BOX Connectors

[GummiSolar]

View attachment 223003

View attachment 223004

Ok

 

[GummiSolar]

Can we get a picture in the direction of arrow to see the profile of this crimp?

View attachment 222995

 

[42OhmsPA]

These crimps appear to be done with the correct hardware and with the correct die / tool. I bent the cable away from the connector so you could see that the conductor is indeed copper. The cable feels very similar to the welding cable I usually use.

View attachment 223003

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Nice crimps.

Not nice crimps

https://diysolarforum.com/attachments/img-20240617-wa0010-jpg.223005/

 

[GummiSolar]

I have a pair of the cables from DOCAN. They are labeled as follows:

EV Cable 50.00mm2 -40°C - 125°C 1500VDC XLPE MYSUN

That is the cable wire, not the connectors. If anyone can tell me the manufacturer name of the connector it would be greatly appreciated

 

[B-ManFX4]

That is the cable wire, not the connectors. If anyone can tell me the manufacturer name of the connector it would be greatly appreciated

I cannot find a name or number on the connector. I think they may be provided as a completed assembly by MYSUN.

There's quite a few here: MYSUN EV Products Web Page

 

[wpns]

Looks very similar to the Degson 250A connectors that EG4 uses in their PowerPro batteries.

 

[Brucey]

So 42OhmsPA called it, your solar installer failed to properly crimp this connection, causing overheating and melting. Prob could have pulled it completely free witha good tug. Luckily it didn't proceed to burning your house down. He owes you a new cable and an apology. Any heat damage to the fuse that connects to that bus?

No crimp


good crimp

 

[GummiSolar]

I don't think that the crimp is theproblem. There is obvious crimping going on. Other wise the metal would be completely round. I think the problem might be the connector was damaged higher up or the plug was not inserted all the way in. Look at the pictures I have attached. There is no heat damage where the crimp is!

 

[D71]

These pictures below are what seen generated when looking at Seplos connectors on AliExpress. There are indeed several versions. The quality may suffer.

I agree with 42OhmsPA called it as most likely - root cause in combo. I think future thermal imaging monitoring service - system have a market…alerting ppl to hot spots. Someone just needs to do it at an affordable price and sell it
.
Dimensions. AliExpress is good about offering spec - dimensions for somethings. Name on connector from aliexpress.






Amphenol Surlok Plus 250amp rating.

 

[42OhmsPA]

I don't think that the crimp is the problem. The is obvious crimping going on. Other wise the metal would be completely round. I think the problem might be the connector was damaged higher up or the plugs was not inserted ask the way in. Look at the pictures I have attached. The us no heat damage where the crimp is!

I think the heat would build at the top of the connection, I'm far from an expert on this just regurgitating what I've read here.
A damaged connector could cause and the connector not fully inserted would certainly cause it.

 

[GummiSolar]

Is it possible it wasn't fully seated/locked in?

Yes, that is what I think too.

 

[GummiSolar]

I think the heat would build at the top of the connection, I'm far from an expert on this just regurgitating what I've read here.
A damaged connector could cause and the connector not fully inserted would certainly cause it.

Yes, I suspected damage that wasn't easily detectable to anyone? Or the connector wasn't seated all the way. I have asked for a connector spec sheet from Apexium and Docan. Neither can provide such! This is a buyer beware situation about the connectors!

 

[GummiSolar]

The other option would be not completly pushed on. Or with the OP stacking batteries and doing a Z wire configuration (in accordance with the manual/common practice) verse using bus bars the connection just plain overheated. Thermal image of wires in this configuration are pretty stark - the first and last connection from the box to the inverter is taking current from the whole stack

To the OP - you have a stack of batteries - was this connection on the top/bottom or somewhere in the middle?

And it could just be a bad connector on the wire.

Hopefully they send him a new wire and box connection to fix the issue.

and IMO were I to do a stack of batteries I would use bus bars for all the connections to keep the current even and I would connect my uplinks between the 1&2 and 3&4 battery to keep the balance dead even. This is per the thread about paralleling batteries and the answers are not intuative but the math is.

The connector that was damaged was the top box that was connected to the inverter.

 

[marionw]

I have never been a fan of a "non bolt" connection. I want a crimped lug (properly crimped) seated against a bus bar (or connector) with a bolt that has been properly torqued and where there is sufficient contact area to ensure proper current capacity.

Had the issue been caught earlier the culprit might more easily be identified. It looks like the problem persisted long enough that heat buildup across multiple "joints" has masked the actual fault.

 

[GummiSolar]

For Seplos boxes, that's great, I assume there are full data sheets for thermal, installation, and torques specified somewhere.
Do you believe the OP's connector is futronics?

They are not Futronics! One issue I have with Apexium and Docan is when I asked for a spec sheet or a manufacturer name they can provide nothing to me. This is now a buyer beware situation!

 

[GummiSolar]

well, i've been told that basically Docan relabels the Seplos boxes, and i don't see any noticable differences at first glace in the connectors themselves
the data can be found here : https://futronics-conn.com/product/fsp-14-0-signal-core-90-right-angle-connectorip54b/

The connectors provided with the Apexium DIY boxes are not Futronics connectors.

 

[GummiSolar]

OK, google image search actually did something useful for me.
Kuka Cable looks like a match. Maybe.
View attachment 222882View attachment 222884
Is it possible the Apexium connector on the box was mated with a different brand right-angle cable assembly?

No, the connectors were provided with the Apexium diy box.

 

[marionw]

What happens with these "spring loaded" "Flexcoils finger technology" when the springs are subject to heat. Do they lose their "spingyness" and therefore their "gripping" power thus further decreasing the effective contact (and increasing resistance)

 

[42OhmsPA]

I cannot find a name or number on the connector. I think they may be provided as a completed assembly by MYSUN.

There's quite a few here: MYSUN EV Products Web Page

These might be it.

[Hot Item] Automotive Hv 200A Battery Storage 1 Pin of 8mm Plastic DC Power Right Angle Plug Connector for 50mm2 Cable

Type: Socket Terminals Material: Copper Application: Battery Pack-Motor Character: High Current Species: Plug Production Process: Injection Molding

m.made-in-china.com

 

[ricardocello]

These might be it.

[Hot Item] Automotive Hv 200A Battery Storage 1 Pin of 8mm Plastic DC Power Right Angle Plug Connector for 50mm2 Cable

Type: Socket Terminals Material: Copper Application: Battery Pack-Motor Character: High Current Species: Plug Production Process: Injection Molding

m.made-in-china.com

The Renhotec connectors only have two “stripes” on top, the OP connector has three.
Also, the backshell piece is not smooth.

 

[robbob2112]

The connector that was damaged was the top box that was connected to the inverter.

Which means that connector had 100% of the current from the stack running through it. So any minor imperfections would cause your problem in a hurry.

Crazy me, I would replace all the connectors and box feed-throughs with a bolt version or the Futronics. The other thing I would do is add bus bars and go from each battery to that.

Did anyone else notice the wires in the cable were not so fine?

 

[42OhmsPA]

So for anyone else following along I emailed Jenny about potentially buying boxes and wanting replacement connectors in case I make a bad crimp...
Replacement are available, from US stock.

@GummiSolar good luck in rebuilding, again I'm glad you caught the problem when you did.
Please ask for help if you are unsure on things.
If I were you I'd order replacement connectors from Docan, get a proper crimper and make some new cables. While you're at it pick up and FLIR camera so you can check all your connections and components for excess heat. My UniT has saved my ass from potential disaster once so far.

I still firmly believe this in not an Apexium or Docan issue. I've never dealt with Apexium, I wouldn't hesitate to order from Docan again, 4 smooth transactions in the past couple years.

I apologize if I sound like an ass, it's not my intention, I get frustrated seeing repeat threads like this that place blame where it shouldn't be placed.

 

[D71]

So for anyone else following along I emailed Jenny about potentially buying boxes and wanting replacement connectors in case I make a bad crimp...
Replacement are available, from US stock.

@GummiSolar good luck in rebuilding, again I'm glad you caught the problem when you did.
Please ask for help if you are unsure on things.
If I were you I'd order replacement connectors from Docan, get a proper crimper and make some new cables. While you're at it pick up and FLIR camera so you can check all your connections and components for excess heat. My UniT has saved my ass from potential disaster once so far.

I still firmly believe this in not an Apexium or Docan issue. I've never dealt with Apexium, I wouldn't hesitate to order from Docan again, 4 smooth transactions in the past couple years.

I apologize if I sound like an ass, it's not my intention, I get frustrated seeing repeat threads like this that place blame where it shouldn't be placed.

I feel the same in some instances.

mouser has a wide selection of what think are better connectors…various amp ratings. Ampenol name which was good yesterday but might be crap tomorrow. Things change in the Global World.

https://www.mouser.com/c/connectors/power-connectors/heavy-duty-power-connectors/?m=Amphenol&series=SurLok

With electricity we are dealing with a pet rattle snake. Unpredictable at times for cumulative effect and more so when take eye off of it or disrespect than we get bitten.


Some Welders use a push in turn dinse adapted cable …the old welders had bolt on cable connectors. I’ve seen the new style burn up. Those new connectors are called dinse plugs and am amazed they were not used for battery quick disconnects. They have actually been used on welders for a long time.

I like bolts don’t plan to be taking it apart on regular basis. Do you?

 

[robbob2112]

If I were to bet, I would also say the connectors brand/style has to match the cable end brand/style. Kinda like the MC4 even tiny differences can be a problem

 

[ricardocello]

While you're at it pick up and FLIR camera so you can check all your connections and components for excess heat.

This is a relatively inexpensive and very reassuring way to sleep at night knowing that the nearly 200A running through the connectors I crimped (rated 360A) will not burn down the house. Strongly recommended. And recheck every few months.