Experience with ExelTech microinverters?

tallgirl

Anyone here use ExelTech's back-of-panel integrated microinverters? They call them "AC Modules", but I don't want to confuse people with terminology they haven't seen.

BB.

Re: Experience with ExelTech microinverters?

I guess this is the product you are asking about?:

http://www.exeltech.com/pvacproduct.htm

According to their brochure, they are 120 VAC 216 watt output units:

http://www.exeltech.com/downloads/acmbrochure.pdf

Interesting...

-Bill

tallgirl

Re: Experience with ExelTech microinverters?

BB. wrote: »

I guess this is the product you are asking about?:

http://www.exeltech.com/pvacproduct.htm

According to their brochure, they are 120 VAC 216 watt output units:

http://www.exeltech.com/downloads/acmbrochure.pdf

Interesting...

-Bill

"Interesting" is an understatement.

I've been pointing clients at Enphase for nano/micro grid support, but the panels from ExelTech are stupid-simple to install. I think the AC feed is a piece of 8/2 UF NM-C that's connected via insulation displacement connectors -- very pointy, hurt my finger when I pushed on them really hard. I am not smart sometimes .

Which means run AC feeder from distro panel location through 1 or 2 pole breaker depending on system voltage (each panel is half a 120/240 split-phase system) to panel location, then in a J/B, splice to 8/2 (or whatever) UF, run AC under panels, THAT IS ALL.

Oh, and the panels don't much care -- they can probably support 120/208 Wye, which would be sweet for AC coupling a 3-phase OutBack stack.

One of their engineers is supposed to be sending me a 250K line data file so I can get the simulator up and running ahead of product support. And unlike Enphase, their data is OPEN. The PLC data gets converted to either 802.11g or 802.15 (Zigbee). In 802.11g mode, the data is broadcast using UDP to port 6010. Meaning, no extra Envoy's or hacking PLC data streams.

n3qik

Re: Experience with ExelTech microinverters?

I looked at them a while back on their site when I was looking for an inverter. They sell only to OEM panel manufacturers only.

From their FAQ:

I’ve got solar panels already. Can I purchase Exeltech PV AC Module inverters and attach them to my existing solar panels?

No. Once again, safety regulations require that the Exeltech PV AC Module inverters be attached to the PV module (solar panel) by a UL-approved facility.

Will Exeltech PV AC Modules ever be sold separately?

No. They will not be sold separately to end-users. Exeltech PV AC Modules will be sold as individual units only to manufacturers, resellers, and others who are authorized by UL (or similar Nationally Recognized Testing Laboratory such as ETL, TUV, and others) to attach the Exeltech PV AC Modules to the rear of PV modules for resale to the general public.

tallgirl

Re: Experience with ExelTech microinverters?

n3qik wrote: »

I looked at them a while back on their site when I was looking for an inverter. They sell only to OEM panel manufacturers only.

Right, because they are selling the panel and inverter combo as an AC panel. It's not a DC panel =and= AC micro-inverter, it's a single unit.

techntrek

Re: Experience with ExelTech microinverters?

Yet on that first link it sounds like they are trying to sell directly to the consumer, with language like:

Have a system already? Add PVAC Modules anyway!
PVAC Modules work with existing solar equipment.

Use Exeltech PVAC Modules to expand your system.
Lack sufficient space for a full-sized system? No problem!
PVAC Modules can be installed in any number to “fill in”
odd-sized areas. Simply install as many as you need for
100% coverage.

drees

Re: Experience with ExelTech microinverters?

Looks like they have the best warranty on the market - 20 year limited warranty on the entire AC module.

Also like that the system completely shuts down at night - no night tare losses at all!

It appears that with each module capable of 212W or 1.8A - how are they able to pass NEC by allowing up to 10 panels per circuit? I would have thought that this would only allow 8-9 modules / circuit depending on how you do your rounding.

I'm not crazy about the clamp on piercing connectors they use to attach each module to the home-run cable...

techntrek

Re: Experience with ExelTech microinverters?

Also, the installation instructions seem to be geared towards the user.

http://www.exeltech.com/downloads/pvacinstallation.pdf

tallgirl

Re: Experience with ExelTech microinverters?

drees wrote: »

Looks like they have the best warranty on the market - 20 year limited warranty on the entire AC module.

Also like that the system completely shuts down at night - no night tare losses at all!

It appears that with each module capable of 212W or 1.8A - how are they able to pass NEC by allowing up to 10 panels per circuit? I would have thought that this would only allow 8-9 modules / circuit depending on how you do your rounding.

I'm not crazy about the clamp on piercing connectors they use to attach each module to the home-run cable...

I don't believe it's #12 wire, so it's not likely to be a 20A circuit. Also, remember that 20A on #12 is for 60C terminations. Get rid of the 60C terminations and you pick up more amps with 75C terminations.

halfcrazy

Re: Experience with ExelTech microinverters?

ExelTech has a neat product We got to play with the stuff in Wisconsin this year looks like a very simple inverter and well potted. the connectors are cool and worked well when we played with them.

I understand the issue not selling direct to the market but requiring a panel manufacturer install them may have been partly UL related

tallgirl

Re: Experience with ExelTech microinverters?

halfcrazy wrote: »

I understand the issue not selling direct to the market but requiring a panel manufacturer install them may have been partly UL related

100% on the "UL related".

Still, would be nice if they had one that had DC inputs -- Enphase has a proprietary data format, ExelTech is completely open. Enphase locks you into all of their services and gadgets, ExelTech doesn't. ExelTech could give Enphase a run for their money if they wanted to, plus they make standalone / backup inverters that are pretty phat.

(Now where is that 250K line file they sent me that I'm supposed to be writing software to parse ...)

drees

Re: Experience with ExelTech microinverters?

tallgirl wrote: »

I don't believe it's #12 wire, so it's not likely to be a 20A circuit. Also, remember that 20A on #12 is for 60C terminations. Get rid of the 60C terminations and you pick up more amps with 75C terminations.

Good point - it's very likely 90C rated wire.

But the specs that I read indicate that each circuit of up to 10 modules should be protected by a 20A circuit. So with each module capable of 1.8A - it doesn't add up. Sounds like you should be using a 25A breaker.

tallgirl wrote: »

Still, would be nice if they had one that had DC inputs -- Enphase has a proprietary data format, ExelTech is completely open. Enphase locks you into all of their services and gadgets, ExelTech doesn't. ExelTech could give Enphase a run for their money if they wanted to, plus they make standalone / backup inverters that are pretty phat.

Yes, the open data format is a huge plus, IMO. Since I already have Enphase inverters, I am hoping that the additional competition entices them to open up the Envoy for DIY data gathering for those inclined. Otherwise, there does seem to be enough people working on reverse engineering the product (Wish I had a bit more free time). I just don't see how locking up most of the data hurts them for the typical customer who could care less... Sure some of the geeks out there would likely forgo their monitoring/subscription, but I really doubt it would happen in any significant numbers.

tallgirl

Re: Experience with ExelTech microinverters?

drees wrote: »

Good point - it's very likely 90C rated wire.

Yeah, but likely 75C terminations. 90C wire is great, but I'm not seeing a lot of terminations rated 90C in the more or less "consumer" space. Hell, there's 105C wire out there -- don't ever want to work on a wire that's 105C!

But the specs that I read indicate that each circuit of up to 10 modules should be protected by a 20A circuit. So with each module capable of 1.8A - it doesn't add up. Sounds like you should be using a 25A breaker.

Ah, yeah. You could send the engineers an e-mail if you have their address. I'm still stuck on other software. And taxes. Need to do sales tax this weekend ...

Yes, the open data format is a huge plus, IMO. Since I already have Enphase inverters, I am hoping that the additional competition entices them to open up the Envoy for DIY data gathering for those inclined. Otherwise, there does seem to be enough people working on reverse engineering the product (Wish I had a bit more free time). I just don't see how locking up most of the data hurts them for the typical customer who could care less... Sure some of the geeks out there would likely forgo their monitoring/subscription, but I really doubt it would happen in any significant numbers.

It would probably be easier to parse the HTML the Envoy puts out.

I was supposed to get a couple of inverters and an Envoy on loaner, but that fell through. I'm tied up with wind turbine monitoring work, and the driver code for the ExelTech inverters, for the next couple of weeks or I'd offer to take some on loaner

The really sweet thing, unless you have too many routers in your LAN, is that the ExelTech data is broadcast by UDP on port 6001. All you need is something to listen to UDP traffic on that port and you're golden. My little logger will probably have code to translate to and from TCP so it can be shipped over the Internet, but that's a project for ... next week

solar_dave

Re: Experience with ExelTech microinverters?

tallgirl wrote: »

The really sweet thing, unless you have too many routers in your LAN, is that the ExelTech data is broadcast by UDP on port 6001. All you need is something to listen to UDP traffic on that port and you're golden. My little logger will probably have code to translate to and from TCP so it can be shipped over the Internet, but that's a project for ... next week

A simple way to do this is use netcat to listen and pipe to another netcat to send, one UDP and one TCP.

tallgirl

Re: Experience with ExelTech microinverters?

solar_dave wrote: »

A simple way to do this is use netcat to listen and pipe to another netcat to send, one UDP and one TCP.

Well, yeah. But that works on ... Linux. Much easier to write a Java program that runs on Linux, Mac OS X =and= Windows 8) than track down netcat for all of them.

techntrek

Re: Experience with ExelTech microinverters?

Ugh. Java. < big grin >

tallgirl

Re: Experience with ExelTech microinverters?

techntrek wrote: »

Ugh. Java. < big grin >

Well ... I have my issues with Java as well, but it runs on everything.

When I was much younger and far more naive, I thought C was the most wonderful language in the world. Still do -- I've written something on the order of 500KLOC of C in my life (I type fast ...), but C doesn't run on everything, or else you have to fight with the compiler, or O/S, or runtime, or ...

With Java, if there is a JRE / JDK, you're 90% of the way done. It's bloated, slow, and otherwise annoying (not a big OOPL fan), but it passes the "Git 'er done!" test. And at my age and level of crankiness, I'm big on "Git 'er done!"

solar_dave

Re: Experience with ExelTech microinverters?

techntrek wrote: »

Ugh. Java. < big grin >

Ditto! Hate Java for most things, just to bloated and inefficient, plus it likes to hide its internals from the OS with the JVM setups. Personally for portable Perl is much nicer, while not the fastest, most decent OS just come with it out of the box. (ugh on Winders too)

I feel the need, the need for speed! Use 'C'. Me likes lots but does require good design and planning and testing to prevent poor memory management, but it gets you close to the machine, has minimal footprint and can be complied several different ways to alter machine optimizations. I just wrote a system to process 1 million lines of live data every 10 sec in 'C' in real time, and the thing flat screams on HP DL365 G6 server.

techntrek

Re: Experience with ExelTech microinverters?

Unfortunately where I work most management thinks Cobol is #1, Java is a close #2 and everthing else is... not Cobol or Java. So far I've managed to avoid both for the last 11 years.