Howdy,

I've got two questions:

(1) My two Suntie's will be about 50' from my computer. Can the OptoIsolators carry RS-232 signalling that far? I've got plenty Cat 5, twisted pair.

(2) Is it better to attach the opto isolator to the back of the PC or should I attach it out at the Suntie? I take it that if I mount it out by the Suntie, I'll have to have an electric outlet available for the power supply?

Thanks in advance,

Alan

I've done 50' with no problem.

arnold

Put it the opto at the Suntie , this way the Comm run isn't carrying the switcher noise

RS232 , should do 500 ft +

If it is USB powered then it is usually easier to put it closer to the computer.

arnold

That is why I only recommend a walwart powered one now , I have had feedback that using the usb ones wasn't reliable , especially when more than one inverter was being monitored.

Cross-talk in the wires run due to the switcher noise being coupled in the cable

Thanks for the help. I'll be ordering the RS-232 opto isolator in the next few days.

I've been using the NuDam RS 232 Opoto isolators which are USB powered. My current setup is a 7.5 kw system with three Xantrex Sun Tie ST2500 inverters with the upgrade.
I installed this monitoring system over a year ago and have been unable to get useable data. The distance from the inverters to the monitoring computer is approximagely 135 ft. The problem appears to be the switching noise in the CAT 5 cable over that run.
Solar Guppy worked with me to resolve the problem and now there appears to be a pratical solution.
I am curious as to the source and installation of the newly recommended optoisolators at the inverter.
This information is not currently in the fishbowl owners manual.

Please re-read the sticky in this FishBowl Forum.

It was because of your problems I ONLY recomend the walwart power isloators now and the isolaters need to be AT the inverter.

http://www.solar-guppy.com/forum/viewtopic.php?t=164

click on EXTERNAL POWERED OPTO CLICK HERE