Chinese 300w MPPT Grid-Tie inverter
 

http://www.powerinverter-kr.com/wbyy/grid/300Wgrid2.jpg

At $99.99 these things are much cheaper per-watt than Enphase units.

NEW ~300w GRID TIE INVERTER 12v/110v ?solar panel? - eBay (item 170440750792 end time Feb-08-10 20:35:19 PST)

For the price of a single Enphase, you can get two of these units.
They would seem to have a lot of the advantages(MPPT) of the Enphase units, but limited by not being water proof.
I couldn't see spending $199.99 on one of their 600w inverters,
since the 300w unit seems to be the perfect match for big 230w PV panel.

Link to China site and 230v units

I'll bet people who are running off-the-grid systems could use these 300w
units to grow their system if their big inverter is already near max.

Anyone seen these being deployed in North America?
I would be interested to know if the quality is ok..

The red switch next to the plug appears to be a voltage toggle -- does that mean it can be either 120v or 240v? Also, it is not hard wired, so you would have to build a waterproof box that had a plug box in it, I guess?

That's what it looks like, but if you check their website, they list both 110 & 230 volt (300w) models.

When I was buying a waterproof box at Lowes, I saw some larger sized boxes.
http://ecorenovator.org/forum/projec...r-project.html
But, now that I think about it, heat build-up might be a problem with a sealed plastic box.

Good find! This may be just what I'm looking for.

Is it UL listed, or even safe to use?
how much does the enphase cost?

My guess is, no UL, so it's likely a product for hackers..

The Enphase units can be had for about $1 a watt.
Enphase Micro Inverter M190-72-240-S11 MC3, 190 Watt, 54VDC/240VAC
And, they have all the right labels (UL) etc..

If they aren't UL listed, you can't legally connect them to the grid.

That's why I said, "it's likely a product for hackers".

This type of inverter might be useful for people living off the grid, or people who
have part of their home (like the garage) off the grid.

It might only require a simple battery and 12VDC to 120VAC inverter to Boot it up.
Or anything that could supply a fake grid voltage to the unit.

Once the inverter was running (with PV supplying the juice), the power
could be used for any kind of load within it's power range.

Like running an AC on those really sunny days.. :)
(Might have to stack a few inverters)..

~~~

Or, if someone had an off-the-grid system and the inverter section was
maxed out, so that no more panels could be added, these mini-inverters might be very useful.

One unit could be used with each new 220W PV panels added to the old system.
But the DC from the new panels goes right to the new inverter and it's AC output goes right into the house wiring..
The new panels bypass all the old system's DC hardware and the new AC power syncs up with the old system's output.

A cheap and easy way to add-as-you-grow your PV system..

~~~

DIY people who hack their own hardware know they risk insurance not paying
off if their fire or other damage was caused by non-approved devices.

That's the main reason why Hams with older non-UL listed power supplies
should disconnect those devices when they are not in use..

I wouldn't plug in anything until I was happy it wasn't poorly made, as to be dangerous.

When I get a new wall-wart, I always monitor how much heat it's producing, before letting stay plugged in, unattended..

I have tossed out or modified a few cordless phone chargers..
(When you pick up your cordless phone, it shouldn't feel hot). :eek:


Humm, I wonder if my gas powered back-up generator is UL listed??? :confused:

The big concern with grid connected inverters is that they need to shut down instantly if the grid goes down. The latest UL requirements cover this requirement and are more stringent than previous requirements. This is a safety concern, not for the homeowner or user of the inverter, but everyone else who might be connected to or working on the grid in that area. A concern is not burning down a house, but electrocuting a lineman down the road.

It seems like to much trouble to do all of your own testing to make sure that a product like that is safe to use and to try to rig it up in such a way as you can use it and have it meet code.
Even more so when there is a sealed weather proof product that does meet code.