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General Category => General Discussion => Topic started by: krementz on December 15, 2017, 11:13:54 AM

Title: Emergency: Classics stopped charging
Post by: krementz on December 15, 2017, 11:13:54 AM
I have an emergency. I have two MN Classic 150s charging from two identical arrays of 2500w each.

At 9:30am 12/12, one of my Classics stopped charging, the other continued on till darkness. There has been zero cumulative watt/hours since.

Even with very dark weather, I usually get some trivial charging showing during the day. I have never seen daylight-hours flat zero. The weather has been overcast, not heavy rain.

My urgency is I am a 5 hour drive, then $120 air taxi to get to the location. I cannot imagine what would "kill" two chargers. No lightning or thunderstorms. I am down to 69% SOC, even with systems turned off. There are no errors reported on the SMA inverters.

Could a PV circuit breaker tripped? How? I find it hard to believe that both chargers would die suddenly. Are there are settings that could be changed. I have looked at them remotely; all seem normal.

Ideas/suggestions?

Title: Re: Emergency: Classics stopped charging
Post by: ClassicCrazy on December 15, 2017, 12:08:38 PM
How do you remote monitor them ?
What was the history before the failure ?
Hard to diagnose what could have happened - don't have a clue to what the installation is on your setup . Could be anything . Seems like onsite visit is your only venue .


Larry
Title: Re: Emergency: Classics stopped charging
Post by: WillEert on December 15, 2017, 01:09:40 PM
I have had the Classic Mode turn itself to "off" for some unknown reason. This has occurred a few times. I don't know how you monitor your system or what you can see remotely but I can tell you that if the mode is "off" the Classic stops producing power.

Will
Title: Re: Emergency: Classics stopped charging
Post by: krementz on December 15, 2017, 01:23:50 PM
The Classics are connected to a pair of SMA 6048 inverters and the SMA Webbox. My small Outback system runs the data communications gear, so I can monitor and control the big SMA system remotely, even when the SMA system is in Standby (inverters off). The charging (Classics) work regardless of the SMA system being in Standby.

The system has been active (not standby) since I was last there, about 2 months ago. I turned the SMAs to Standby to reduce parasitic losses since they weren't charging.

Through the Webbox, I can change about 160 Parameters, and view about 125 Spot Values (voltages, SoC, amps, PV watts in, etc.). There have been no warning or errors.

When you said the Classics went "off", what did you do to restart? Any idea why? Is there any non-physical-button way to restart/switch to on?
Title: Re: Emergency: Classics stopped charging
Post by: WizBandit on December 15, 2017, 02:05:51 PM
Do you have our LOCAL APP running and connected to the Classics?  You can get a RESTING code for a reason if so.
I suspect winter sun angle, overcast and more overcast and a lack of Irradiance necessary for energy production to be a possible issue.
Title: Re: Emergency: Classics stopped charging
Post by: krementz on December 15, 2017, 02:41:06 PM
I do not have the Local App, only the SMA software.

Even with very low irradiance, I have never seen ZERO production, except in very heavy rain (or nighttime). Weather has been semi-cloudy to clear.

Do you know if the resting code is sent to the SMA software?

Title: Re: Emergency: Classics stopped charging
Post by: WizBandit on December 15, 2017, 06:23:54 PM
I don't think the RFR is available from the SMA.
Resting can be from hardware failure, software, input out of spec.
Hard to tell you why they are resting without more information.
Maybe the Arrays are gone?  I had one setup where that was the issue.
They ended up down at the bottom of the hill.
Title: Re: Emergency: Classics stopped charging
Post by: mike90045 on December 15, 2017, 08:05:18 PM
Has there been any wind - could both arrays have been damaged or stolen ?  know anyone who can take a look to see if a tree fell over onto the arrays ?
Title: Re: Emergency: Classics stopped charging
Post by: Westbranch on December 16, 2017, 03:08:56 PM
I posted this a few days ago but???? I guess it's an Ether Post... :o

If you do not have a connection to the LOCAL App  or a connection ENABLED TO MyMidNite, which gives you constant data flow to a Data Base ,

I suggest it would behoove you to dig around and see how to set it up so you can gate a few hours of data  via the backup system (good idea BTW)...
thinking about it quickly, I suspect you could load "the APP" on a RPi and save the last sent data to your Monitoring PC...??

also I had one Classic stop charging one winter and reset from a 24V system to a 12V system. took weeks of back and forth  due to NO Net link...

I guess you have a trip coming,  All I can say is take 2 of everything you MIGHT need... 2 Classics?

and load the Local App on your laptop before leaving...

Good Luck
Title: Re: Emergency: Classics stopped charging
Post by: krementz on December 16, 2017, 03:38:51 PM
SMA confirmed they are not helpful.  :(

There has not been any significant wind, no trees nearby, arrays are ground-mounted with massive foundations, and local aircraft have not reported any strangeness.

I will try to get out after Xmas, weather permitting. I will try to get the direct to MN software connected. I had an issue last time, but don't remember what it was.

BTW, since I have 2 150s, do both have to have ethernet cables/IP addresses, or will connecting one will talk to both? I think I only have one open outlet on the router.
Title: Re: Emergency: Classics stopped charging
Post by: Resthome on December 16, 2017, 04:45:58 PM
Are your Classics set to reboot every night at midnight? If not that is surely a setting you want to make for any remote site.
Title: Re: Emergency: Classics stopped charging
Post by: ClassicCrazy on December 16, 2017, 09:47:05 PM
Quote from: krementz on December 16, 2017, 03:38:51 PM
SMA confirmed they are not helpful.  :(

There has not been any significant wind, no trees nearby, arrays are ground-mounted with massive foundations, and local aircraft have not reported any strangeness.

I will try to get out after Xmas, weather permitting. I will try to get the direct to MN software connected. I had an issue last time, but don't remember what it was.

BTW, since I have 2 150s, do both have to have ethernet cables/IP addresses, or will connecting one will talk to both? I think I only have one open outlet on the router.

Are your Classics in Follow Me ?  Seems like I read somewhere that Classics in Follow Me can accumulate errors and need a hard reset ever so often to clear them all out and put them back to normal.  But really not sure if that is your issue or not.
Will be great if you get either remote Local Status App or at least My Midnite remote reporting so you can see what is going on when you aren't there.

Larry
Title: Re: Emergency: Classics stopped charging
Post by: boB on December 17, 2017, 03:16:13 AM
Quote from: ClassicCrazy on December 16, 2017, 09:47:05 PM
Quote from: krementz on December 16, 2017, 03:38:51 PM
SMA confirmed they are not helpful.  :(

There has not been any significant wind, no trees nearby, arrays are ground-mounted with massive foundations, and local aircraft have not reported any strangeness.

I will try to get out after Xmas, weather permitting. I will try to get the direct to MN software connected. I had an issue last time, but don't remember what it was.

BTW, since I have 2 150s, do both have to have ethernet cables/IP addresses, or will connecting one will talk to both? I think I only have one open outlet on the router.

Are your Classics in Follow Me ?  Seems like I read somewhere that Classics in Follow Me can accumulate errors and need a hard reset ever so often to clear them all out and put them back to normal.  But really not sure if that is your issue or not.
Will be great if you get either remote Local Status App or at least My Midnite remote reporting so you can see what is going on when you aren't there.

Larry


No need for Follow-Me when the SMA Sunny Island is commanding the Classics into Float and Bulk-Absorb.

I was going to say that when you get there, if the Classic(s) have crapped out, you can temporarily connect the PV directly
to the battery positive to get some kind of charge into the system.

When the Classic is resting you can connect the PV+ directly to the Batt+.  But  ONLY if the Classic is not running.

Also check the PV input voltage.  If a Classic should blow, it will ~usually~ short the input and so you would see
somewhere around zero volts input.

Hopefully it is something real simple.

boB

Title: Re: Emergency: Classics stopped charging
Post by: Westbranch on December 17, 2017, 01:50:45 PM
Krementz, I just read another post in a discussion about 2 classics using Follow-me and boB wrote the following , I don't know if it applies:


There is also another mode we use but is for when using the SMA inverters which act as masters
to control each Classic's charge voltage and report back to the Sunny Island
.  This shouldn't have
anything to do with your system but in the MISC menu under COMM sub-menu there is a setting
for that.  You COULD try fiddling with that but it should be good.  You have to reboot the Classic(s)
to have that take effect though.

Title: Re: Emergency: Classics stopped charging
Post by: krementz on December 17, 2017, 05:12:55 PM
Westbranch - Thank you. I will look into that when I get out there. From memory, I know there is an SMA mode (which I am in), but do not remember any other details.

boB - Do you know if are there any parameters to set on the Classic that are NOT transferred from the Sunny Island? For example, on the Classic I believe I can set the Lat/Long for sunrise/sunset, but that cannot be set from the Sunny Island.

I reflashed the Classics with a new firmware a few months ago, and just let the SI fill in all the parameters. Are there any others that should be looked at that the SI does not manage?  I assume setting auto-restart at midnight can (should be) enabled.
Title: Re: Emergency: Classics stopped charging
Post by: krementz on January 06, 2018, 11:23:30 AM
Out and back too quickly due to adverse weather...

Both Midnites were in OFF mode. No errors apparent. I changed to ON mode, rebooted everything, and every thing seemed to come up good. I changed the Auto-reboot to ON.

Had to leave, but remotely could see system charging normally for 2 days. Turned off inverters remotely to conserve power during adverse weather. Restarted inverters today, nice sunny and very cold day, zero watts!  Any ideas?

Can the Classics "freeze", I mean from temperature? The temperature is around 0ËšF. When I was using the MNGP, each button push seemed to take 5-15 seconds to respond and update the screen. Later when I got the Workshop up to about 40-50Ëš, they responded normally.

Title: Re: Emergency: Classics stopped charging
Post by: ClassicCrazy on January 06, 2018, 10:47:00 PM
My Classic is out in the shed and has been 0 F or below for a week or more and also in the past have never had any problems.
I have the MNGP for it inside though but I have seen LCD displays that were cold take a long time change so could be the cold effects that.

Not sure why your Classic would not be charging . What was the battery voltage ? Did you ever get the remote Local Status app working or get it to report to MyMidnite ?

Are those Classics in Follow Me ? Seems like I just heard someone else have problem like that with theirs when it was in follow me mode.

Larry
Title: Re: Emergency: Classics stopped charging
Post by: estragon on January 12, 2018, 03:51:35 PM
Are ground fault and/or arc fault enabled (I think both are by default)?  IIRC, these need a manual reset, a daily automatic soft reset doesn't clear them.  I think I had to mess about a bit with sensitivity to avoid nuisance trips. 

FWIW, my classics also get cold (0f or lower), and they run fine.  They warm themselves up when charging, and are probably happier not getting too hot.  LCDs in anything will slow down a lot in the cold.

Just a thought, but I wonder if the cold might have loosened a connection somewhere enough to trigger a fault?
Title: Re: Emergency: Classics stopped charging
Post by: krementz on January 13, 2018, 01:17:25 PM
Thanks everyone for their comments.

I was able to get one of the Classics connected to Mymidnite, and have been monitoring both Classics via the SMA software tools. I have not been on-island since Jan 4.

After several days of nada, everything seemed to start working again on January 9. The batteries stated warming up (from 11ËšF to above freezing today) and the air temperature stayed above zero, but that should not have made much of a difference. I would expect the Classics to work below zero; the specs say they functions down to -40. The autorebooting seems to be functioning.

There does not seem to have been any ground or arc faults as I have not reset them.

So still a bit of a mystery, but the chargers are working as expected and therefore no crisis. Next time I go out I will get the router ports opened so I can see the Classics remotely, and figure why there is no MAC or ID code on the 2nd Classic. The Midnite software is much more friendly and useful than the SMA software.

I'm adding more PV and a third Classic in the spring, so it's good to get all the software and comm equipment running properly.

Title: Re: Emergency: Classics stopped charging
Post by: krementz on January 19, 2018, 03:19:01 PM
Finally got back out.

Everything seems to be fine. Still had the no MAC and no Device ID on the MNGD, even after multiple power-off reboots. Someone discussed looking via the Local App, and voilá, there they were. Entered, and now have MyMidnite reporting on both Classics. Yay.

Thanks to everybody giving me ideas.
Title: Re: Emergency: Classics stopped charging
Post by: Westbranch on January 19, 2018, 05:16:15 PM
your comment about using the L App reminded me (loosened some cobwebs) of a post some time back that the \MNGP and the L App were not always reporting the same value for MAC and Device ID... 

good that you got it all up and reporting.