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Off topic - Inverter issue

Looks like an overheat issue to me. There are several things that will cause that like a loose connection, poor quality or faulty hardware, improper wire sizing, etc. How did you come up with 2/0 cable as the size you needed? it is supposed to be able to carry full DC load when the inverter is at full rated output. This should be noted in the installation manual. The important variable is the total length of the circuit, not just the distance of the inverter from the battery bank. This is determined by adding the lengths of both the positive AND negative runs.

I trust that these through-bulkhead connections aren't directly above the battery bank? That would not be a good location for bus bars, chargers, inverters, or other devices due to gassing off. This is likely mentioned in the installation manual.
 
makomark said:
Will have to look later....no access to the pics from current location...
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Thanks guys I spoke to BlueSeas and Promariner and both think this was simply a corrosion issue and nothing more. I'm not 100% convinced. The negative cable right next to it is fine and I did use dielectric grease plus it has an insulating boot. I think I'm going to replace it and use a copper or bronze lock washer instead of the stainless one it comes with. When I'm done, I'm also going to spray corrosion block on the whole thing.

I confirmed the sizing and I'm way over spec'd on the wire so I'm sure it's not an overheating issue. My inverter is only 1500 watts and based upon the total length (including negative) I could run a 3,000 watt unit. Maybe it was a little loose? I doubt it but can't rule it out. The pinkish color of the cable ends bugs me....

Two electrical comments. I did not ground the case to the AC bus bar, Promariner said that would not be the cause. I also did not size up the negative cable from the last battery to the engine block. Not a bad thing to do but also not a culprit for what you see here.

Bob
 
definitely a bad connection at one of the feed-thru's....and for that kind of money, I'd use a different realization.

I personally prefer feed-thrus with enough stud to have double nuts on each end. Biggest reason is you really don't want the "body" of the feed-thru to have any role in maintaining electrical and mechanical integrity of the connection.

The other question is what material are the cable end connectors made of? If they are tin plated copper, should be adequate....

Other than that, I think your redo approach is sound...I would just add that I would take voltage drop measurements once I was done, before sealing the connections and record the results in the log...It will help if you every have to repeat the exercise..
 
Mark, do you know of a different/better manufacturer? I searched for a while and the ONLY one I found was the same.
i did only use one nut so the back of the connector was bottomed out on the face of the connector. Maybe a better setup would be:

Nut...washer...connector....washer....nut. That way the connector would sandwiched between the two washers and backed up by a nut on each side. I think I'm going to use bronze washer and nuts this time. The cable ends are tin plated copper and so is the pass thru stud.

thanks
Bob
 
Bob, you made the following comment in post #4;

I also did not size up the negative cable from the last battery to the engine block. Not a bad thing to do but also not a culprit for what you see here.
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Typically speaking, an Inverter's Pos and Neg cables will make a direct battery bank connection.

The Pos cable will incorporate the correct size circuit fuse separating it from the + Batt post.

The Neg cable will make a direct - Batt post connection (unless a Batt Montoring system Shunt Resister is being used)!

The inverter's Pos cable should not be passing through your MBSS!


.
 
Rick, to clarify my boat doesn't have any battery switches (came from the factory that way). I ran 2/0 cables directly to the +/- connections on my inverter battery bank. On the pos side I added a 150a ANL fuse. The negative cable I was referring to was the final battery ground which either goes to my negative bus bar or engine block. I'm going to the boat today and will check.


I just know that my boat originally came with two start batteries and one house battery. The house "battery" is now four 6v batteries. I haven't sized up any of the those original negative cables. All the connectors are nice and clean but original. The two engine start batteries haven't changed amperage wise so really just the house bank I was thinking of. I have a hydraulic crimper, I should just make up all new ones. My boat is old enough that the copper wasn't tinned.


Alright, I'll change the cables!! Why do you have to jump all over me like that! :)
 
Rick, I don't know. None of the Trojan Internationals came with them from the factory. I have an emergency start button at at the helm if needed and the start batteries are automatically combined when starting. I saw that note in the wiring diagram just yesterday. And, my house loads are split between my two start batteries roughly between port and starboard.

In spite of this setup, it's never been an issue for me in the five years I've owned the boat. In a way, I like not having an MBSS as it's one less point of failure or certainly confusion. I have a battery monitor for all three banks and I've moved the heavy draw house loads onto my four 6v batts. I can go two full days on the hook which is about as long as the family can take it anyway. If something really crazy happened and I ran down both start batts to the point I couldn't start the engines, I have jumper cables on board and could jump start off the house bank. I haven't even been close to that point.

Bob
 
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