It has happened again

[Jason Wilkinson]

Hi to all, Today we has high winds and i suspect the turbine oversped (my batteries measured 13.7 volts, i don't as yet have a dump load circuit and for the past month it was not needed ) MY system is used primarily to run the outside lights, totall watts  15 x 13watt cf bulb approx 4 to 5 hrs daily giving the turbine enough time to recharge the batts,Today for the 3rd time there was this loud "pop" and smoke from the inverter, surprisingly it is still working.I should add ,the inverter output is 700watts max  the model is (MAGNETICS USA  MAG 190; 700 WATT POWER INVERTER)after the 1st experience i noticed it was able to powera 6.6 amp power drill  which it could'dt do before. Should i be concerned  or are those popping sounds it's method of protecting itself from  overvoltage?

 ps During a  gale the tail swings  but never that far to turn the blades out of the wind yet i've seen the blades face other directions as the wind shift. (i don't know how to link the past posting to this one

      Jason

 

[Flux]

Not much to go on.

13.7v will not bother any respectable inverter. What we really need to know is the input voltage to the inverter during a gust. If you are not seeing above 13.7v on the battery then if the inverter is directly connected to the battery terminals there should be no problem. If part of the wiring is shared with the turbine wiring then you may have troubles with volt drop. Similarly bad connections could cause similar trouble.

If the input to the inverter doesn't exceed 14.2v then that is not your problem. Beyond about 14.2v some inverters will shut down ( aggravating the problem in this case). Beyond about 16v you start to run into limits within the inverter and the pop and smoke could be from input capacitors. You should never reach that voltage unless you have very high charge currents and a very small or faulty battery.

It is possible that you have a faulty inverter and the trouble is not related to input volts. If you have increased the rating I can only guess that you have blown part of the protection circuit. No it is not self protecting and I think you must accept that it is going to die soon.

Check those input volts directly on the inverter during gusts. If all is in order then you may have a rogue inverter or there is something going on with ground loops or something that would be impossible to guess at with the limited information.

Flux

[SparWeb]

You didn't say if the inverter's "pop" occurred as you measured 13.7V or not.  Anyway, the inverter may have been experiencing more than that if you don't have a correctly calibrated meter.  Is this a 200$ Fluke meter, a 5$ chinese meter, built into the inverter, or a panel meter of some kind?  

Making other assumptions about your system, it is possible that 5 minutes after reading 13.7V, the batteries could be up to 15 or 16 Volts, and that could let out the magic smoke, too.  You said this mill is unregulated, so the voltage can go up and down very rapidly.

[Lumberjack]

Untill you get a dump load, burn some power. Leave the lights on.....

[Jason Wilkinson]

Thanks for the response, the voltage was read about 2 mins after the pop, ie batt voltage,I disc. the inverter and batt. and the  voltage increased rapidly to 25 to 30 volts just before i hit the kill switch, after the wind returned to near normal and batt and inverter were reconnected there was a slight siren sound not as loud as the "bell & whistle alarm" No the batt voltage never read as much as 14v, i have a small "mastercraft digital vom" AS i'm writing this now,the wind is picking up again and i just measured 13.10 to 13.16vdc at the batt and the amp meter is reading 5amps, only the green pwr light is on ,ijust turned the lights on and all are lit ,the fan is on on the inverter, the amp meter shows neg -5amps, it is possible the inverter is faulty , some nights the lights come on about a min after the switch is thrown, but they do come on

  Thanks again  Jason

[Jason Wilkinson]

will leave some lights on till the morning and read the batt voltage etc etc

 Jason

[Basil]

Smoked my 1000 watt inverter when a friend plugged a 1300 watt heater in it. It smoked like crazy. It bowed the fuses inside and melted a relay. Replaced the fuses. Did not replace the relay. It still works. He overloaded it and the shut down did not work.

[frackers]

Most inverters these days (especially the modified sine ones) run multiple DC-DC converters to get about 1.5 times the output voltage. These multiple sections all run in parallel and provide a cheap way of getting from low to high volts without each section having to run at a particularly high current.

The high volts is then switched (using a bridge driver most likely) to the output terminals to provide the 'squared up' AC to the load. This final stage will be putting the 150volt on the converters first one way and then the other to the output but since it only has to provide about 6 amps, the devices (MOSFETS perhaps) can be quite small and don't need a massive heatsink if its a modded sine inverter.

Sounds like you have blown up one of the many parallel converters so your total load capability will be reduced, even though it still basically works.

[Jason Wilkinson]

THanks for that info, i'll keep an eye on it

        Jason (Barbados w i )