Hello,

I would like to write my own logging program for the STXR. Thanks to the Fishbowl software and manual, I have an optically isolated serial connection from a laptop to the STXR, and the Fishbowl software works great.

Can anyone enlighten me on the COMM settings for the STXR? I tried various speeds at 8N1, but it was clear I didn't have it right.

What is the speed data/stop bits and parity?

thanks,
David

It is 8N1 at 9600 baud

It's raw binary streams , not ASCII

ST/XR and XR/UPG are different streams

No one except Me and Xantrex has the info and I can't release to the public due to non-discloure aggreements.

What features are missing in FishBowl that you feel you need to write a custom application ??

[ 11-28-2003: Message edited by: Solar Guppy ]

I am part of an ecovillage residential community which has 14 houses with between 1500-2500 watt suntie XR systems. We do a lot of green building/sustainable technology demonstration projects, so we want a way to log and transform the data on one of our linux servers, and then easily reformat the data on our websites using php.

So the first problem would be that we don't want to have to use a Windows machine. The second problem would be that we don't really want to listen to the inverters all of the time (since when it is dark it isn't doing anything), and finally we can't have physical serial connection to all of the inverters, so we use netport serial-to-ethernets (which in themselves aren't a problem, I tried one of them with your program and it works great).

So I guess the bottom line would be that we don't really want to run windows machines, what we really want is to virtualize the connection to all of the inverters, and run a single linux server to compile the data.

BTW-your program is a very nice piece of work.

Well, if the data is binary and you aren't allowed to release the specs, that is perfectly understandable. We will make an attemtp to decide it, and if we can't then I guess we will either find a way to use your program or we will turn our engineering to something else...

Thanks for the quick reply. Happy Thanksgiving!

FishBowl Does everything you need already !

You can run as many instances of FishBowl you want , one for each inverter , let it run 24/7 , the data is only logged to disk when the inverter is awake.

Use an old PC , run win98 and have it make the data files , then just batch the files to the linux server for all post processing. You can get old computers for 39 bucks ... end of problem

If you need a copy of windows ... I can help

I have a Linux server running all the time, so I wouldn't mind running a version of Fishbowl on it, so I don't have to have a second computer turned on all the time running Fishbowl. As recommended here, I bought a laptop off ebay ($250) just to run Fishbowl. It only burns 10 watts continuously -- so it's not the end of the world. My Linux server, a standard PC, burns about 60 watts continuously, which is high enough to burn more than a kilowatt-hour per day. I'd like to switch the Laptop to Linux to save power; otherwise I'll just have to buy another laptop for my Linux server. It's a lot cheaper to save kilowatts than to generate them!

BTW, Fishbowl is an awesome program!! I've been able to almost double my winter solar power generation by seeing the graph of daily power generation. Before I had Fishbowl, I thought my low winter power generation was due to the short days and clouds. With Fishbowl, it was easy to see I was losing a lot of output to tree shadows. The low angle of the sun in late autumn, winter, early spring brings a lot of shadows from trees into play that really cut power output. A few hours of tree trimming makes a big difference. I also raised the angle of my roof mounted array, as recommended in this forum, from 23 degrees to about 30 degrees (with seasonal adjustment twice a year) which helped quite a bit. I live in the Bay Area at about 37 degrees of latitude, so it would be better to raise the angle more, but I'm afraid of what a big windstorm might do at the higher angles -- it also wouldn't look too good.

Thanks Henry for the forum and Fishbowl to help me make these improvements!

hello all, in lieu of spending another $80 for the opto-isolator recommended, i already have a box full of opto-isolator chips i'd like to make use of. Are the tx, rx, gnd signals the only rs-232 signals being used? i'm asking if cts or any of the other rs-232 signals are being used. are the signalling levels used on this serial port in the inverter still within the +/- 12V rs-232 spec (with reference to whatever ground is being called)? a second question. not trying to be stubborn, but it was described that the gnd for the serial port is connected to the negative side of the pv cells, not earth ground. isn't the negative side of the pv cells directly shorted to the earth ground connnection inside the inverter? i'm just trying to get a feel for how this is set up.
okay, now i'm on a roll. so another question. any chance that xantrex will make the communication protocol available? i notice they allow and support communication through terminal emulators on some of the other inverters. i noticed some people wishing to use linux. myself, i'd like to connect a little mcu (hey look, my shift key does work) datalogger to it instead of leaving a pc out in the garage. just a request. thanks in advance.

First , understand this

If you don't want to spend the 80 bucks for the opto , DON'T USE MY SOFTWARE , it is a CONDITION of use ... GOT IT !!

There is No IF's about this ... the reason Xantrex didn't release a PC logger/viewer was for liability reasons ... I have , with the explicit requirement of using the opto isolator .. Sorry if this seems though , but it is the times we live in ...

PV minus is connected to earth ground thru a GFI breaker ... if it senses any current flowing thru this path (ground fault) it opens the connection and is tied to the DC breaker which trips the DC in. When th GFI trips , PV minus can become any potentional and if you have a PC grounding it thru the comm line can fry the PC. There is also considerable high freq noise from the inverter that gets coupled to PV minus ... again can seriously destroy th RS232 port or worse. It also can be a ground loop from the PC to the Inverter , going thru the CPU card , which can damage the CPU card.

The only connection from the Suntie on th db9 port is data pin 2 and pv minus , pin 5 ... there is no other available signals for powering anything , hence why a adapter powered opto is needed

You have to ask Xantrex about the comm. protocal , it is there IP , not mine.


Your little mcu idea won't work unless you seriously filter the data ... the comm stream is 36 bytes second or about 130K hour .. you'll need 2 megabyte a day ... why bother , a used 50 laptop (running win98) can do everything for you using the software as is ....

thanks for the guidance and advice mr. solar guppy. i'm excited to get your software up and running. i'll splurge with the 80 bucks and do it right. you know how it is, 'finishing' up the installation of my system by nickel and diming hardware,connectors, etc. has added up to quite an amount. i was excited about monitoring my system through serial port, and then learned i have to buy something else.
you've got a tremendous site you've put together. i'm sure it is well appreciated. thanks.
brian

Hi Brian,

Glad your going to proper route

I hope your pleased with your new system and enjoy using FishBowl to monitor it's production ... It never gets old for me !

Henry