Help my solar controller caught on fire

[bmklawt]

Please help,

I recently installed a SunSaver 6 solar controller and this past weekend after having been set up for camping for a few hours all the 12 volt power went out. I leisurely moseyed on back to the fuse panel see what had happened, as soon as I opened the bathroom door I could smell burning rubber. I opened the closet door to get at the fuse panel and smoke billowed out, I opened the door to the fuse panel and all I could see through the smoke was bright electrical sparks and fire at the solar controller.
I had my brother go unplug the camper and I just starting yanking wires out of the solar controller, even after pulling wire, unplugging and removing fuses the solar controller just keep on burning. I had to leave after that, I couldn't hold my breath any longer and I could not breathe through the smoke.
When I finally go back in the camper to survey the damage there wasn’t much, the solar controller looked a little charged. I would have thought with that much nasty stinky smoke the controller would be completely melted.

Any way what the hell did I do wrong to make this thing have a melt down.
Below are photos of the box and a schematic of the wiring.

Would much appreciate your help on this

My first thread on this matter

[bmklawt]

By the way I didn't blow a single fuse

[Dwight]

Your charger maybe sized too small.....the better ones on the market are...

Morningstar Corporation » TriStar MPPT

[arodriguez60]

It looks like the load wire is the one burnt. Why would you have a load on a 6 amp system? I doubt that you would have much of an excess of power. That amount of solar is just enough for one battery and none to spare.

[zedex]

I think something shorted out behind the sunsaver plate.

[thecatsandi]

The Sunsaver 6 is only meant for 6 amps. You do not wire a load in the a trailer. The load comes off the battery. The way you have it wired your DC load runs through the Sunsaver. Hence the "fire"

[pgr32e]

Your running the entire 12V load through the charge controller, I don't really think that's the way to do it. T'was mine, I'd run the load for the fuse panel from the positive bus and just have the charge controller feed the bus. That way, heavy power demand will come directly from the batteries and not through the controller.............Phil.

[bmklawt]

Thanks everyone for the information, as you can see I know just enough to make me dangerous.

I think my controller , 6A, is of the right size, here are the specs to my solar panel.

Module Catalogue Number BP250/1 BP250/2
Typical Peak Power (Pmax) 50.00W
Voltage @ maximum power (V mp) 17.00V
Current @ maximum power (I mp) 2.94A
Short-circuit current (I sc) 3.22A
Open-circuit Voltage (V oc) 21.20V

Here is how I believe it should be wired, please correct me if I am wrong.

[thecatsandi]

That looks much better. You should have a fuse in the line from solar panel to the Sunsaver and a fuse from the Sunsaver to the main buss. The solar panel fuse should be near the solar panel.
If you plan to add more panels you should look at a much larger controller.
I have a Morningstar Tristar PWM 45A controller. I am running just under 20A at full sun. It runs nice and cool.

[eksine]

Originally Posted by arodriguez60

It looks like the load wire is the one burnt. Why would you have a load on a 6 amp system? I doubt that you would have much of an excess of power. That amount of solar is just enough for one battery and none to spare.

Why would he put a load on a 6 amp system? why wouldn't you? how else does he use the low voltage disconnect if he didn't? the failure was from the charge controller, the OP did nothing wrong.

[eksine]

I wouldn't listen to these guys, if you connect straight to the battery than you no longer have the low voltage disconnect to protect your battery bank from being destroyed. you are supposed to wire it to your charge controller which you did so you did nothing wrong. the fault is only through the controller and nothing else, 6A was just too low and the controller is a POS, I have the 10 A version used with a 100 watt mono panel connected to a 2/0 cable which used to be for my car's sub amp, it didn't fail for the few months I used it.

Originally Posted by bmklawt

Thanks everyone for the information, as you can see I know just enough to make me dangerous.

I think my controller , 6A, is of the right size, here are the specs to my solar panel.

Module Catalogue Number BP250/1 BP250/2
Typical Peak Power (Pmax) 50.00W
Voltage @ maximum power (V mp) 17.00V
Current @ maximum power (I mp) 2.94A
Short-circuit current (I sc) 3.22A
Open-circuit Voltage (V oc) 21.20V

Here is how I believe it should be wired, please correct me if I am wrong.

[switz]

We used the Morningstar TriStar 60 MPPT controller in the Classic with 800 watts of solar panels. We will add another 100 watt panel in May. The Blue Sky 3024iL is sufficient for the five 100 watt panels on the 23D. We sized the solar charge controller and associated wires to the output of the solar panels.

[alano]

thecatsandi is correct, you shouldn't connect the load to the battery. Doing so probably causes current to flow through your solar controller and not directly from the battery.

Another problem I see is that you do not have adequate clearance to allow proper air circulation as required in the manual. Either you should relocate your controller or open up the top of the enclosure to allow airflow.

The controller you selected should work fine once you get a replacement

[scamp]

Maximum load 6-10 amps ,you have how many 20 amp fuses +other fuses on the load side !no wonder it melted! Plus we need to know wire sizes, and were they come from ,I think we need the wiring schematic from the manufacture. As I think it can be wired different to work but all loads should come from the battery not the charge controller ,I think this controller has a feature ( load side ) to control a small load such as a ( one ) light or fan 6 amps or maximimum 10 depending on model, also you need to due a better job of wiring as I see you have a wire insulator part touching metal your just looking for it to rub through ,this is a trailer going down bumpy roads .also you have the jumper in for a sealed type battery this jumper must be removed if your charging a flooded lead acid battery as there is a different charging voltages for sealed versus flooded,this didn't cause your problem ,but could be another down the road.

[lewster]

Has anyone noticed the date of the original discussion??

[BoldAdventure]

Originally Posted by lewster

Has anyone noticed the date of the original discussion??

I was wondering why someone dug up this ancient post.

[scamp]

The snowball only gets bigger as you roll it in the fresh wet snow ! What a mess wiring and snowball! Thank Lewster or pointing out the date

[AWCHIEF]

New post was made by a new member starting out by insulting other members and apparently not reading the entire thread. Go figure.

[BoldAdventure]

Originally Posted by AWCHIEF

New post was made by a new member starting out by insulting other members and apparently not reading the entire thread. Go figure.

He should fit right in then.

Also he used a cable from his "car's amp" which means he's a knowledgeable expert.

See, just keeping the snowball going here.

[lewster]

Not my place to comment on the OP's wiring job....... I leave that to you guys!! :-))


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
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Master Tech Energy Systems, Inc.
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