Classic 200, Aux/relay, any prefered relay?

[clockmanFrance]

Hi,

I wish to use my, purchased 2013, Midnite Classic 200, Aux/relay in Diversion mode to control AC Coupling of 3 Sunny boys GTI.

Is the Aux 1 relay 12v output rated for continuse and constant on off use. ?
Do you have a prefered design/spec for this 12v relay which I will use to switch my power relay On.

Once a set point of battery charging is reached a power relay will activate and shut off the AC to the Sunny Boys. Well thats the idea.

It seems that my recent purchase of a SMA Sunny Island 6 and its so called AC Coupling is at best ‘flaky’, and I constantly have issues with the SI.  So I will use the Midnite Classic 200, that charges the same 48v battery bank that the SI uses, to control the SB's.

This guy in Australia seemed to sum up the SMA SI…..

“It might be worthwhile to put the SBs back on standard specs (ie not ramping on frequency change), tell the SI not to change frequency relative to battery voltage and program an auxiliary relay in either the SI or the regulators (I'd pick the regulators â€" more reliable) to switch a contactor feeding the SBs at the bulk charge voltage. The DC regulators can handle the absorb and floats.
I've heard a couple of tales of woe about trying to train SI/SB setups and it seems they are a bit flaky.
If you do as I've suggested at least you'll have reliable output frequency and 95% of the generation from the SB will make it to the battery.
Maybe check the firmware updates in a year or two when SMA work out how to train their inverters and have another go at it then”……………………….

“It appears to be very hit and miss still, very disappointing. Like you not the first time I've seen some issues, I thought they had would have resolved it with current models, disappointing.
A pity other ways have to be added in an attempt to overcome an issue that should not be there, anymore.  "patching" should not be required.”

More on this steep learning curve and the SMA SI saga/story at……………….

http://forums.whirlpool.net.au/forum-replies.cfm?t=2397087

https://www.navitron.org.uk/forum/index.php/topic,24521.0.html

http://www.fieldlines.com/index.php/topic,148681.msg1033244/topicseen.html?PHPSESSID=20fafef163b64bcc9f0fc73bd3a022a2#msg1033244

http://www.photovoltaikforum.com/sma-insel-wechselrichter-off-grid--f46/si6-oh-11-springt-zu-60-hz-wenn-der-akku-geladen-i-t106825.html

Thanks

[Halfcrazy]

Yes it is good for continuous duty, For situations like that we tend to use Solid State relays

[clockmanFrance]

Thank you for the information.

I am still struggling with SMA, and they still insist there is nothing wrong with the SI.

Thanks to 'Sparweb' for the analysing and collating the SD Data, The SI comes with a SD Data card function and data doesn't lie, I am told 

'Sparweb's' Notes.....

There is an interruption of 30 minutes around noon on 3 May which I presume is the SI being disconnected.  Apart from that, operation of the SI is continuous, in a manner of speaking.  The logs are continuous, I should say.

The battery estimate of SOC is reset to 100% twice, for no apparent reason.
The battery voltage does not have a "bulk-float" pattern like mine does.
The battery charge current is repeatedly switching + and - during the 5th of May, but it could just be busy machines on a sunny day.  The rest of the charge pattern looks typical of weekday-weekend usage.

Of course, the inverting drops out many times.  The frequency graph looks worse than the Inverter Voltage graph - and it's getting flakier all the time.  It jumps to 60Hz and parks there for hours.  Other times, it jumps back and forth between 60Hz and 49Hz.

[Jacotenente]

Fascinating graphs. The graph of the frequency does not look encouraging. I hooked up a static, digital frequency meter to my system and have been watching it. When heavy loads (2,000 watts or so) are applied to the inverter...the frequency doesn't move. Dunno what the deal is with your system. Mine is rock solid...voltages, watts, and frequency. FWIW, dunno what is causing a freq drop like that.

[clockmanFrance]

Latest reply from SMA Service Germany.......

"We understand that you’re not quite satisfied with the current situation in your system.
But the Sunny Islands now give out an inverter frequency up to 60Hz if there is still energy going into the batteries.
This is not a mistake of the current firmware version."

So there you are, all New Sunny Islands will go to 60HZ, and this is now normal.

I am just fed up with this, so now seeking my Money back as the SI does not do what it is supposed to.