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Sandero · 17-08-2014, 17:57

Update...
I bought a new inverter... Xantrax ProWatt 1000.
When I removed the old one... I found sever corrosion on the neg 12v terminal. 12 pos was fine. The neg had over heated.. and melted the plastic house of the connector. Obviously this WAS the problem.

The inside of the unit looked fine... and it does work when the voltage demand is not very high... obviously the heavy 12v neg was way under performing. I don't know if a spare connector body is available. I could fabricate something. But it's hardly worth it.. a rainy day project.

The question in my mind is what's up with the 12v neg? I had a problem with the 110v neg wiring as well... with overheating perhaps starting from corrosion.

Why the neg? This makes me think there is some fault in the wiring perhaps. And if there is... I haven't a clue as to how to find it short of completely rewiring both a 110 and the 12v systems or at least checking every single wire. No signs of corrosion on any small wiring.

irwin37 · 17-08-2014, 18:45

You may have a poorly crimped lug on the neg lead, or the lug was never tightened properly, both will cause it to overheat. You also may have dissimilar metals such as aluminum lug with copper inverter studs which could cause corrosion. If any of whats mentioned has caused the first inverter to fail it will happen again with the second inverter unless you fix the cables to. Have the inverter cables and lugs looked at by a pro, Its worth it in the long run as the next time it could mean a fire. Also 110 AC does not have a Pos & Neg wire but has both a Neutral & Hot wire (Black being hot), if you have corrosion of any wiring than it needs to be addressed as every point of corrosion can cause both inconvenience and in some cases dangerous conditions. Be safe, have someone with experience look at it.

**Ex-Calif** · 17-08-2014, 18:50

Quote:

Originally Posted by Sandero

My Xantrax 1000 watt inverter seems to be dying. As soon as a few small loads are on.... it shows a low voltage signal and apparently does not produce any AC current. Works for a small load like a cell phone charger but not for a lap top.

I suspect it's something that can't be easily / economically fixed and it's time to replace it.

Has anyone else experienced this sort of behavior from a Xantrax inverter?

Any replacement suggestions? I want to keep it to below 2KW?

I am positive the inverter has failed. There are lots of moving parts inside an inverter that wear out and in the history of boating there has never been a bad ground on recently installed wiring.

Please buy a new one. Send me the old one and I will properly dispose of it for you.

**Ex-Calif** · 17-08-2014, 18:58

Quote:

Originally Posted by Sandero

Update...
I bought a new inverter... Xantrax ProWatt 1000.
When I removed the old one... I found sever corrosion on the neg 12v terminal. 12 pos was fine. The neg had over heated.. and melted the plastic house of the connector. Obviously this WAS the problem.

The inside of the unit looked fine... and it does work when the voltage demand is not very high... obviously the heavy 12v neg was way under performing. I don't know if a spare connector body is available. I could fabricate something. But it's hardly worth it.. a rainy day project.

The question in my mind is what's up with the 12v neg? I had a problem with the 110v neg wiring as well... with overheating perhaps starting from corrosion.

Is the DC conection a ring terminal or what? How was the connection assembled? Properly crimped? Properly soldered? Is it a marine quality ring terminal? Is it marine quality wire?

Take a couple of pics.

Oh, and seriously. If you want to sell that old inverter PM me.

mitiempo · 17-08-2014, 19:05

Quote:

Originally Posted by Sandero

....what's up with the 12v neg? I had a problem with the 110v neg wiring as well... with overheating perhaps starting from corrosion.

Why the neg? This makes me think there is some fault in the wiring perhaps. And if there is... I haven't a clue as to how to find it short of completely rewiring both a 110 and the 12v systems or at least checking every single wire. No signs of corrosion on any small wiring.

How long were the wire runs - positive plus negative? What gauge of wire was used?

Terra Nova · 17-08-2014, 19:08

Quote:

Originally Posted by Terra Nova

Sounds like a bad connection--could be faulty ground.

Quote:

Originally Posted by Sandero

...I found sever corrosion on the neg 12v terminal...Obviously this WAS the problem...

Glad you found the problem.

S/V Illusion · 17-08-2014, 19:24

Quote:

Originally Posted by Terra Nova

Glad you found the problem.

and the lesson learned...

Quote:

Originally Posted by Sandero

"All the wiring is rather new and I seriously doubt a voltage drop from wires or connectors."

transmitterdan · 17-08-2014, 20:05

Quote:

Originally Posted by Sandero

Update...
I bought a new inverter... Xantrax ProWatt 1000.
When I removed the old one... I found sever corrosion on the neg 12v terminal. 12 pos was fine. The neg had over heated.. and melted the plastic house of the connector. Obviously this WAS the problem.

The inside of the unit looked fine... and it does work when the voltage demand is not very high... obviously the heavy 12v neg was way under performing. I don't know if a spare connector body is available. I could fabricate something. But it's hardly worth it.. a rainy day project.

The question in my mind is what's up with the 12v neg? I had a problem with the 110v neg wiring as well... with overheating perhaps starting from corrosion.

Why the neg? This makes me think there is some fault in the wiring perhaps. And if there is... I haven't a clue as to how to find it short of completely rewiring both a 110 and the 12v systems or at least checking every single wire. No signs of corrosion on any small wiring.

Pictures would help. A 1000W inverter draws about 100A max. Xantrex recommends AWG 0 wire which requires special compression tools to make a proper crimp. High current connections that overheat due to lack of sufficient compression or insufficient bolt pressure can look a lot like corrosion. A common scenario goes like this:

1) Ring lug or compression terminal isn't tight enough or is too small for the current.
2) Connection warms up under load.
3) Bolt expands slightly relaxing the pressure on the ring lug.
4) Less pressure causes more heating.
5) Process runs away until the connection is red hot.

When the metal gets red hot it oxidizes and then when it cools is easily mistaken for corrosion.

An infrared thermometer is a good tool to check connections periodically for unusual heating. The infrared sensor can quickly and safely check temperature from a distance. It's a good maintenance procedure to check for changes in temperature of high current connections every month.

Also, are there any batteries close to this terminal? If so, gas escaping from the battery can cause corrosion.

sailinglegend · 18-08-2014, 03:28

Quote:

Originally Posted by Sandero

...When I removed the old one... I found sever corrosion on the neg 12v terminal. 12 pos was fine. The neg had over heated.. and melted the plastic house of the connector. Obviously this WAS the problem.....

I saw a very similar problem on a Victron with the AC wires not being tightened properly in the screw connector which burnt up the plastic.

You don't have to be a marine electrical engineer to identify faults on a boat.

barnakiel posted earlier:

- open it,
- clean it,
- smell it (yes),

If anything looks or smells like burning, replace this part.

Simple investigation like this is always worth it, but do take extreme caution with AC and make sure any shorepower is disconnected. Cleaning up the Neg connection may solve the problem - in my case I used a typical marine "bodge" using a 30 amp chocolate box connector with large wires re-soldered to the mother board. Yes it took 4 hours to do the job properly, but it saved over $2000 on a new inverter!

Sandero · 18-08-2014, 04:04

Clarifications:

The wires to the inverter are tinned #2 copper (about 5/16" Ø of copper).

The 12v pos connection to the battery was through a 150 amp ANG fuse with crimped on lugs (not specially done). The length is about 10'.

The fuse is wired about 12" to a main 12v pos buss and that to the battery about another 2'. OAL run is about 13'

The cable connections to the ProWatt are NOT lugs but the stripped core is inserted into a hole and secured with a screw which compresses the wire strands.

The heating of the connection melted the plastic part which contained the screw connector.

Only the 12 Neg wire showed signs of corrosion *green* oxidation for an few inches. 12v pos looked new.

No signs of corrosion at the 12v neg buss.

The unit was in a dry location.

No batteries close enough to out gas.

The replacement was only a few hundred dollars and it was not worth fixing the old one.

transmitterdan · 18-08-2014, 05:27

The wire is not big enough. Use 0 gauge minimum size. Also, the wire is too long. For 13 foot total distance you should at least double the gauge of wire. But it would be better if you could find a way to shorten the run from inverter to batteries. Be sure you are counting the entire run length from inverter to battery.

I have seen this problem quite often. For some reason it's hard to believe that such large wire is required for inverters. But it is.

**Ex-Calif** · 18-08-2014, 06:10

if you aren't comfortable with this you should hire an installer.

Here is a cut and paste from the Xantrax PROWatt 1000.

(The table not included recommends 2AWG for a 6 or 8 foot run)

You really need to get this thing closer to the batteries.

Quote:

•Use 4 AWG copper (90º C insulation rating) as the smallest DC cable

•size. This will minimize the voltage drop between the battery and the

•inverter. If the cables cause an excessive voltage drop, the inverter may

•shut down when drawing higher currents because the voltage at the

•inverter input drops below 10 volts.

•Keep all cables as short as possible, and ensure that each cable between

•the inverter and the battery is no longer than 4 feet (1.2 m).

•If you must use longer cables, choose a larger diameter cable such as

•2 AWG, and use appropriate crimp connectors.

•Do not use aluminum. It has about 1/3 more resistance than copper cable

•of the same size, and it is difficult to make good, low-resistance

•connections to aluminum wire.

transmitterdan · 18-08-2014, 07:42

Quote:

Originally Posted by Ex-Calif

if you aren't comfortable with this you should hire an installer.

Here is a cut and paste from the Xantrax PROWatt 1000.

(The table not included recommends 2AWG for a 6 or 8 foot run)

That's not what I see in the table. Table I highlights size 0 cable for a 600W inverter. Below the table it says: "Note: Xantrex recommends a size 0 cable with a maximum cable length of 6 feet (1.8 m)."

The OP's installation is for a larger 1000W inverter at twice the run length so it probably should have larger wire.

I agree that an experienced installer would be a good idea. But they are hard to find these days. And in NYC are probably ridiculously expensive.

This company (Marine Wiring, Boat Cable and Electrical Genuinedealz.com) will make up cables for inverter installations. They use proper sealed lugs and hydraulic crimpers. They can build the cables you need to exact length with adhesive heat shrink. They also sell the proper fuses as well. Getting the fuse and cables is the hard part. After that a DIY installation can be as good as the best professional and better than most.