ebay grid tie inverter question

**russ** · 04-10-2014, 01:00 PM

Originally posted by NSsolar

Hello, this is my 1st post here, and I signed up here to hopefully get some info about installing a grid tie inverter into my existing small solar panel system.

I've been looking at those cheap grid tie inverters on ebay and wondering if they actually work for a small 320W system such as mine is.

Such as this one: http://www.ebay.ca/itm/300W-500W-100...item4abb28a173

So my question is will this device actually dump electricity into my home and save my power bills a bit or not?

Are these garbage? Yep - not legal to use in the US or Canada - look at the plug even - a European style plug

Are the SAFE? The last thing I need is a fire! Who knows - since the vendor knows they are illegal to sell to you they have no reason to be worried about quality or safety.

I talked to the local power company and they said NO WAY, don't hook that up because it is a fire hazard, and if I wanted a grid tie inverter installed, I would have to pay thousands of dollars for THEM to come connect it into my house breaker panel, and I would have to change my home insurance policy as well.

So what do you think?

I expect your quote from the power company is a gross misquote - talk to people there seriously.

Thanks!

Comments in bold in the original post

**NSsolar** · 04-10-2014, 01:22 PM

Originally posted by russ

Comments in bold in the original post

I guess that means that you do not suggest buying one? LOL

So when you say they are "illegal", what exactly do you mean by that? What can they do?

Are they illegal because they are dangerous, or because they do not work?

**russ** · 04-10-2014, 01:37 PM

Originally posted by NSsolar

I guess that means that you do not suggest buying one? LOL

So when you say they are "illegal", what exactly do you mean by that? What can they do?

Are they illegal because they are dangerous, or because they do not work?

1) They don't meet electrical code in the US or Canada

2) They can't have UL or equivalent listing

3) Since the seller knows they are illegal don't expect them to put any effort into quality.

**inetdog** · 04-10-2014, 01:52 PM

Originally posted by NSsolar

I guess that means that you do not suggest buying one? LOL

So when you say they are "illegal", what exactly do you mean by that? What can they do?

Are they illegal because they are dangerous, or because they do not work?

Based on a large number of reports on the web from people who have tried a wide range of "brands" (often using exactly the same PCB but maybe different components and different graphics on the outside), three things stand out:

1. The do not perform anywhere nearly as well as a legitimate MPPT input grid tie inverter should. The efficiency is a lot lower than claimed in the ads.
2. They fail often, and sometimes with spectacular results. And it is not worth sending them back to China for "repair".
3. There are bad things that can happen when you plug one of them into an ordinary household branch circuit even if they are working exactly as designed.
The National Electrical Code and the Canadian equivalent have extensive provisions on how to hard wire a GTI to avoid these problems, and both require that you start with listed equipment in the first place. Do not trust any specs that do not include the exact words "UL listed" (and even then sometimes that listing only applies to the power cord.) Do not put any faith at all in "approved" "compliant" or "designed to XXX standard" as they mean nothing. Similarly, CE approval (actual or claimed) means nothing in US and CA.

**NSsolar** · 04-10-2014, 02:02 PM

Originally posted by inetdog

Based on a large number of reports on the web from people who have tried a wide range of "brands" (often using exactly the same PCB but maybe different components and different graphics on the outside), three things stand out:

1. The do not perform anywhere nearly as well as a legitimate MPPT input grid tie inverter should. The efficiency is a lot lower than claimed in the ads.
2. They fail often, and sometimes with spectacular results. And it is not worth sending them back to China for "repair".
3. There are bad things that can happen when you plug one of them into an ordinary household branch circuit even if they are working exactly as designed.
The National Electrical Code and the Canadian equivalent have extensive provisions on how to hard wire a GTI to avoid these problems, and both require that you start with listed equipment in the first place. Do not trust any specs that do not include the exact words "UL listed" (and even then sometimes that listing only applies to the power cord.) Do not put any faith at all in "approved" "compliant" or "designed to XXX standard" as they mean nothing. Similarly, CE approval (actual or claimed) means nothing in US and CA.

Thanks again for the info!

So, are we talking specifically only about the Chinese ones, or ALL grid tie inverters in general? I don't care where they are made, as long as they work.

Is there one that you CAN buy that plugs into any household socket without needing to wire them into your breaker panel, or are the ONLY ones that work right the big expensive units my power company was talking about?

**Shockah** · 04-10-2014, 02:11 PM

Originally posted by NSsolar

.................................
I talked to the local power company and they said NO WAY, don't hook that up because it is a fire hazard, and if I wanted a grid tie inverter installed, I would have to pay thousands of dollars for THEM to come connect it into my house breaker panel...............

So what do you think?

Thanks!

Aside from the safety hazards of any plug-in GTI, I think you're missing the most important point:

The POCO owns the grid. Gotta live by their rules.
If they say you need to involve them, that means you CANNOT plug in a GTI without their consent

**Wy_White_Wolf** · 04-10-2014, 02:16 PM

Originally posted by NSsolar

I guess that means that you do not suggest buying one? LOL

So when you say they are "illegal", what exactly do you mean by that? What can they do?

Are they illegal because they are dangerous, or because they do not work?

Plugging them into the wall in not NEC compliant. One could put more wattage into the circuit than the wire could handle. For example lets say you plug a 500W one into a circuit protected by a 15A breaker. Then go a plug 1500W room heater and a few other items into that circuit. You now have the possiblity of 500W plus the original 1800W flowing through that circuit. That's 2300W on wire that was protected at 1800W. Plug 2 or 3 of them into the same circuit and the problem gets worse. Nice way to burn your house down.

You might even find a few of them that are claiming UL Compliant. That just means they built the inverter to UL specs but never sent it in for testing. I even saw one that claimed UL listed. My best guess was that they sent in to be tested with a cord designed to be hardwired to a breaker and later changed to the wallwort plug.

It's not illegal for them to sell them. Just for you to hook them up. About like radar detectors are in several states.

WWW

**NSsolar** · 04-10-2014, 02:50 PM

Originally posted by Wy_White_Wolf

Plugging them into the wall in not NEC compliant. One could put more wattage into the circuit than the wire could handle. For example lets say you plug a 500W one into a circuit protected by a 15A breaker. Then go a plug 1500W room heater and a few other items into that circuit. You now have the possiblity of 500W plus the original 1800W flowing through that circuit. That's 2300W on wire that was protected at 1800W. Plug 2 or 3 of them into the same circuit and the problem gets worse. Nice way to burn your house down.

You might even find a few of them that are claiming UL Compliant. That just means they built the inverter to UL specs but never sent it in for testing. I even saw one that claimed UL listed. My best guess was that they sent in to be tested with a cord designed to be hardwired to a breaker and later changed to the wallwort plug.

It's not illegal for them to sell them. Just for you to hook them up. About like radar detectors are in several states.

WWW

I guess my main concern (aside form the safety issues of course) is whether or not they said it was not permitted because of political reasons (They want to sell you power rather than you make your own!) or because there really was an issue with these kind of units.

Forgive me for not trusting the power company here in Canada, they have lied to me on at least 2 occasions about power saving issues, so that kinda blows my trust with them.

So, if I had a dedicated circuit in my house with a 15A protected breaker that nothing was ever plugged into, and I plugged in one of these grid tie inverters with a 320W solar power setup like I have, would that over load that circuit? Doesn't sound like it would if I use ohms law.

**Shockah** · 04-10-2014, 02:58 PM

Originally posted by NSsolar

I guess my main concern (aside form the safety issues of course) is whether or not they said it was not permitted because of political reasons (They want to sell you power rather than you make your own!) or because there really was an issue with these kind of units.

Forgive me for not trusting the power company here in Canada, they have lied to me on at least 2 occasions about power saving issues, so that kinda blows my trust with them.

So, if I had a dedicated circuit in my house with a 15A protected breaker that nothing was ever plugged into, and I plugged in one of these grid tie inverters with a 320W solar power setup like I have, would that over load that circuit? Doesn't sound like it would if I use ohms law.

You appear determined to grid-tie regardless of the risks to your personal property...
So in that case, PLEASE use a GTI with the "anti-islanding" feature to protect any POCO Line-Man that might be servicing your neighborhood and/or grid.

Anti-Islanding GTI will shut itself down if the grid is shut down. There are times when the POCO will switch the grid off to service it.
You don't want your cheap GTI feeding current to the grid when an un-expecting human is about to touch it, do you?

**NSsolar** · 04-10-2014, 03:46 PM

Originally posted by Shockah

You appear determined to grid-tie regardless of the risks to your personal property...
So in that case, PLEASE use a GTI with the "anti-islanding" feature to protect any POCO Line-Man that might be servicing your neighborhood and/or grid.

Anti-Islanding GTI will shut itself down if the grid is shut down. There are times when the POCO will switch the grid off to service it.
You don't want your cheap GTI feeding current to the grid when an un-expecting human is about to touch it, do you?

I'm not determined to hurt anyone, or hurt my own property, I'm just making sure that the answers I get are not politically motivated, for all I know you work for the power company...lol.

the reason I ask on a forum like this is to learn, and because I acknowledge that someone out there knows more than I do, so, I ask questions, some may sound silly to those who know the answers, some may not, regardless, I've learned something, thank you.

**inetdog** · 04-10-2014, 04:13 PM

Even the cheapest of the plug and pray GTIs have an anti-islanding circuit. But without testing I am not willing to risk either life or property hoping that it works correctly under all conditions.

**Shockah** · 04-10-2014, 04:45 PM

Originally posted by NSsolar

I'm just making sure that the answers I get are not politically motivated, for all I know you work for the power company...lol.

I wish that were the case ...

With our POCO's Executive salaries, I could be bought into generating politically motivated answers

**russ** · 05-01-2014, 01:33 AM

Originally posted by NSsolar

Forgive me for not trusting the power company here in CanadaNothing to do with the power company really - the units do not meet Canadian electrical code.

they have lied to me on at least 2 occasions about power saving issues, so that kinda blows my trust with them. Or else you misunderstood them - or else they misunderstood you

So, if I had a dedicated circuit in my house with a 15A protected breaker that nothing was ever plugged into, and I plugged in one of these grid tie inverters with a 320W solar power setup like I have, would that over load that circuit? Doesn't sound like it would if I use ohms law.

That idea is still adequate to make it your fault if the place burns down.

Units like "plug & play" power jacks are sold by shysters that are not the least bit concerned - basically they are outlaws.

**paulcheung** · 05-03-2014, 11:47 AM

If the house burn down, do expect the insurance company NOT paying your policy as they find every reason not to pay you. and this a very good reason not to pay you.

Cheers.