Can a grid tied inverter be damaged?

[labtek]

Hello to the group and good day.

I had a 300 watt grid tie inverter handling 2 solar panels connected in parallel producing about 70 watts. It was plugged into a house/grid electrical outlet through a heavy extension cord. The extension cord had 3 female outlets; the inverter was plugged into 1 of them. I needed to use my air compressor and I plugged it into one of the other outlets of the same extension cord. After using the air compressor, I noticed that the inverter had stopped functioning. I've checked the fuse and all other connections. It was working before I connected my air compressor to the extension cord. Is it possible to damage the inverter by connecting a high draw AC load in parallel with the inverter AC output? It appreas that the extra load cooked it somehow. If so, I will need to be careful to not connect anything else to the circuit while the inverter is working...Thanks for any thoughts.

[russ]

Is that legal in Canada? A plug in grid tie inverter?

[labtek]

Is that legal in Canada? A plug in grid tie inverter?

Let's say for the present that my very small scale, low end installation is "experimental"and temporary...if I see a useful function for it based on my own results, I will brave any possible arrows from the friendly folks of the local utility....

[russ]

Let's say for the present that my very small scale, low end installation is "experimental"and temporary...if I see a useful function for it based on my own results, I will brave any possible arrows from the friendly folks of the local utility....

We stay away from illegal items on the forum.

[labtek]

We stay away from illegal items on the forum.

You disappont me sir. Why is the forum allowing any advice on grid tied inverters at all if they are illegal? I'm not saying that they are illegal in my jurisdiction, I'm saying that I don't know. I bought the unit in Canada so I presumed that they were legal for them to be sold here. Lots of information on the Internet concerning grid tied inverters. Is it even illegal to speak of them? Sad indeed.

In any event, this post may be useful to others wishing to ask for advice or information on the topic on the forum.

I have no further desire to continue discussing this issue with you. Please continue on with your small mindedness. I'll sleep easier this evening knowing that you are "on guard" sir.

Good bye.

[Naptown]

You disappont me sir. Why is the forum allowing any advice on grid tied inverters at all if they are illegal? I'm not saying that they are illegal in my jurisdiction, I'm saying that I don't know. I bought the unit in Canada so I presumed that they were legal for them to be sold here. Lots of information on the Internet concerning grid tied inverters. Is it even illegal to speak of them? Sad indeed.

In any event, this post may be useful to others wishing to ask for advice or information on the topic on the forum.

I have no further desire to continue discussing this issue with you. Please continue on with your small mindedness. I'll sleep easier this evening knowing that you are "on guard" sir.

Good bye.

There are lots of legal Grid tie inverters available. However not any that plug into a receptacle as your description of yours seems to be.
Here is the issue with them.
First there is a potential to have the live male plug shock someone if touched if the anti islanding fails to work. This would be a function of a defective product.
Second and more importantly is the potential to start a fire.
Because the additional current produced by the inverter could be fed into a circuit that is maxed out that additional current could cause say a 15 amp circuit to allow an 18 amp load on the wires.
This will cause the wires to heat up and potentially cause a fire.
Just because you bought it doesn't make it legal to connect to anything. Where I live it is illegal for me to touch or do any electrical mechanical or plumbing work in my own home. Must use a contractor that is licensed to do the particular trade. However I can walk into any home depot etc and buy any item I wish for electrical work etc.
Selling it is not illegal but my installing it is.

[labtek]

There are lots of legal Grid tie inverters available. However not any that plug into a receptacle as your description of yours seems to be.
Here is the issue with them.
First there is a potential to have the live male plug shock someone if touched if the anti islanding fails to work. This would be a function of a defective product.
Second and more importantly is the potential to start a fire.
Because the additional current produced by the inverter could be fed into a circuit that is maxed out that additional current could cause say a 15 amp circuit to allow an 18 amp load on the wires.
This will cause the wires to heat up and potentially cause a fire.
Just because you bought it doesn't make it legal to connect to anything. Where I live it is illegal for me to touch or do any electrical mechanical or plumbing work in my own home. Must use a contractor that is licensed to do the particular trade. However I can walk into any home depot etc and buy any item I wish for electrical work etc.
Selling it is not illegal but my installing it is.

Thanks very much indeed for the post. I understand what you're saying. Perhaps others reading it as well.

[SunEagle]

Thanks very much indeed for the post. I understand what you're saying. Perhaps others reading it as well.

Weather if it is legal or not where you live I believe you have already have found why those "plug in grid tie" inverters are dangerous. As of now you may have only lost the inverter. The next time you might not be as lucky as a fire may be started.

Now my next question is will your home insurance cover losses of using equipment not allowed or have been determined to be unsafe?

[inetdog]

And, just to get back to the original question, no it is not possible to damage a properly designed grid tie inverter by "overloading" it. The extra power needed will come from the grid, and as the drain increases the voltage on the cord from the grid will drop.
At some point the voltage at the inverter terminals might drop low enough that the anti-islanding circuitry will cause it to turn off.
Now if the motor were to generate interesting voltage transients on the line, a poorly designed inverter might possibly be damaged by that.

[russ]

You disappont me sir. Why is the forum allowing any advice on grid tied inverters at all if they are illegal? Grid tied inverters are not illegal - only the piece of junk you bought seems to be an illegal type.

I'm not saying that they are illegal in my jurisdiction You are in Canada I believe - the electrical code is very similar to the US.

, I'm saying that I don't know. I bought the unit in Canada so I presumed that they were legal for them to be sold here. Lots of information on the Internet concerning grid tied inverters. Is it even illegal to speak of them? Sad indeed. We do not provide instructions on unsafe or illegal "stuff/actions.

In any event, this post may be useful to others wishing to ask for advice or information on the topic on the forum. Someone else trying to burn their house down - don't pat yourself on the back - the topic comes up routinely.

I have no further desire to continue discussing this issue with you. Please continue on with your small mindedness. I'll sleep easier this evening knowing that you are "on guard" sir Tough - nothing small minded about not supporting ilegal and or unsafe actions or equipment.

Good bye.

Message in bold within the text.

[labtek]

Message in bold within the text.

Everything I did was in good faith. I have subsequently learned a lot, especially from others who decided to post back. For you to choose not to seems to go against your mandate (especially as moderator) to share information with others who may not be as "enlightened" as yourself. I class myself as a novice but at the same time, wish to explore this method of electricity generation.

I will not use the inverter (or others like them) ever again, nor would I ever advise anyone else to as well until the technology is safe to use. New technology such as this is frequently used by the unscrupulous to promote the technology when it is not yet ready for mainstream use.

I learned that from others and not from you and that's why I was disappointed.

[labtek]

Weather if it is legal or not where you live I believe you have already have found why those "plug in grid tie" inverters are dangerous. As of now you may have only lost the inverter. The next time you might not be as lucky as a fire may be started.

Now my next question is will your home insurance cover losses of using equipment not allowed or have been determined to be unsafe?

There will not be a next time. Your points are well taken. Agree- the loss of the inverter was a lesson well learned.

[SunEagle]

There will not be a next time. Your points are well taken. Agree- the loss of the inverter was a lesson well learned.

I am glad you understand and thank you for saying so. The last thing I want is to have someone hurt themselves hoping to save a few pennies. Electricity is a great thing and dangerous too. Keep coming back to ask questions and discuss topics. The more you learn the more you can pass on to others to keep them safe also.

[Sunking]

I will not use the inverter (or others like them) ever again, nor would I ever advise anyone else to as well until the technology is safe to use. New technology such as this is frequently used by the unscrupulous to promote the technology when it is not yet ready for mainstream use.

The technology is mature and has been around since mid 1800 used in manufacturing to generate steam. Just like gasoline it is very safe to use and deadly in the wrong hands.

[labtek]

The technology is mature and has been around since mid 1800 used in manufacturing to generate steam. Just like gasoline it is very safe to use and deadly in the wrong hands.

I guess I was referring to inverter technology- in the "old days", inverters were huge, extremely expensive and out of reach for most consumers. When the cheap DC-AC inverters arrived on the scene probably 10-15 years ago, I saw it as a tremendous development. When the cheap grid tied inverters started showing up a few years after that, I thought that it was the turning point that home brewers like me had been waiting for.

No longer would we would be COMPLETELY dependent on the utility grid and/or batteries. We could use the utility grid instead of a battery bank for storage!!. How absolutely appropriate!! No longer would home brew (solar and wind) electricity guys be seen as "tinkerers, lunatics and fools". I must admit that I was distracted by the significance of it all...

The situation with my grid tie inverter was an important lesson for me but a temporary setback. Based on my location on the Canadian east coast and my solar and wind footprint, it lends itself to a solar and wind installation, properly installed according to code. I've seen us go for 6 weeks straight and not see the sun through the heavy overcast but all that time the wind blew...I've also seen 4 weeks with constant sun and almost drought conditions.

In these days of global warming and climate shifts, as citizens of planet Earth, legal homeowner small scale electricity projects may help us survive here.

Thanks to the forum for bearing with me.