Why did a small short knock out my inverters power supply first?

softdown

I was in a dark room and plugged in an old tool with a bad power cord into a GFCI. Seen a small, brief spark...and lost all building power.

I expected the order to be:
1) GFCI that was plugged into
2) Circuit breaker that supplied power.

No...first to cut power was my Outback Inverter. Took me a few minutes to get it going again. It acted like it was quite taken aback.

BB.

First, your AC inverter's output protection is probably many times faster than the standard fuse or breaker (milliseconds to stop inverting vs faction of a second to minutes for a breaker/fuse to break).

Second, GFCI only work on Hot to Earth (green wire) or Neutral to Earth shorts... Hot to Neutral looks just like an "ordinary" AC tool load (albeit with too high of current). And the GFCI will not trip in the case of a true Hot to Neutral short.

Lastly, sometimes devices are self resetting (auto reset breakers, AC inverters that will try X times then shut down until the DC power is reset/manual reset, etc.). Manual vs Auto Reset have their advantages and disadvantages.

Me, I carry a small flashlight (AAA or AA cell) with me.

-Bill

softdown

Great explanation...as usual.

But I don't get this part: "Lastly, sometimes devices are self resetting (auto reset breakers, AC inverters that will try X times then shut down until the DC power is reset/manual reset, etc.). Manual vs Auto Reset have their advantages and disadvantages."

Are you saying that it is likely that my inverter would have auto reset with enough time? How much time do they usually take?

BB. wrote: »

First, your AC inverter's output protection is probably many times faster than the standard fuse or breaker (milliseconds to stop inverting vs faction of a second to minutes for a breaker/fuse to break).

Second, GFCI only work on Hot to Earth (green wire) or Neutral to Earth shorts... Hot to Neutral looks just like an "ordinary" AC tool load (albeit with too high of current). And the GFCI will not trip in the case of a true Hot to Neutral short.

Lastly, sometimes devices are self resetting (auto reset breakers, AC inverters that will try X times then shut down until the DC power is reset/manual reset, etc.). Manual vs Auto Reset have their advantages and disadvantages.

Me, I carry a small flashlight (AAA or AA cell) with me.

-Bill

BB.

I don't know. Try finding the programming manual and see if it has a programmable reset.

-Bill

waynefromnscanada

Re "auto reset" on inverters. My Morningstar SureSine 300 inverters were designed to auto restart 3 times, after which they require a manual restart.
On the other hand, the Xantres Puresine 1000 and 1800 inverters I have, do not have auto restart and must be manually disconnected from their DC power, then restarted. Different designs.