Rev #1856 - OVR Light Activity

[suits]

During my second day running firmware revision 1856 i noticed some odd activity from the OVR Led, that has now led me to other odd findings. I'm curious if any other 1856 users are noticing anything similar or perhaps can offer any idea as to what is occurring here.

As usual, my charge output current to the battery hit the 30amp limit early this morning (838W @ 27.9V) and the OVR lED began indicating such, as it usually would. I noticed later in the morning that the charge current had began to pull back normally, but the OVR LED was still flashing even though the charge had been reduced to 26A (741W @ 28.6V). Shortly after reducing below 26A, the OVR LED returned to off state.

Knowing that the OVR Led monitors both Battery Current, as well as voltage I started looking into the voltage aspect. I have never noticed the voltage any higher than my absorb voltage of 28.8, and the panel voltage throughout was within a 56V to 60V range. Since we now have 30day data logging, I checked the V BATT MAX log for both days and this is when I stumbled upon oddity number two. Both Days the VBATT MAX registers as 29.6V!

That 29.6V I have never witnessed reported by any of my equipment. My inverter never registered a higher Battery voltage than 28.8 at the tail end of the absorb cycle, and the kid never indicated a voltage higher than 28.8. So now i'm left wondering if I'm getting an odd voltage spike for some reason. First step will be monitoring over the next day or so to see if I can register this 29.6v the log is registering.

Anyone else noticing anything similar or have any thoughts on cause ?? (and just to confirm the AMPLMT setting for BATTERY is 30A)

[pobox88]

I have observed the OVR LED flashing at what seemed odd times with version 1811. As far as I can workout, the OVR LED will turn on when the KID has reached its maximum
charging current as set by the parameters you enter. In my case, flooded batteries, 232AHr at 48VDC and charging at 23Amps (the 20hr rate for my battery bank).

Anytime the KID was near the 23A current limit I observed the OVR LED either flashing or fully on. It was telling me the KID was working at my preset maximum charging current.

So far the 1856 version seems to be all good.

PS It isn't really an OVR (overload) indication, more a "I've reached maximum charge current preset"

[ClassicCrazy]

I just looked and I see a 15v high voltage . I have it set to 14.4v for Absorb and Equalize too so shouldn't be that high.
But I have no history - only todays value. That could be because I am using my Kid to take 24v from bigger battery pack and basically just float a 12v agm battery . I am wondering if it needs to see zero volt input in order to know to start a new day so that is why I don't get any data logging ?

Does anyone understand the U-Set Mode and how it's settings work ?

Larry

[suits]

I did find a small bug in the 30 day data logging that may be affecting you as well. On occasion it would only show today's data. When I scrolled to 1 DAY AGO it would show all values as zero's. This only happened once yesterday. I was able to get the history back by scrolling back to TODAY, then trying to go back to 1 DAY AGO again. The second time it showed the values ok.

As of sunrise this morning I am displaying a V BATT MAX of 25.3V so it appears to be ok prior to charging cycle beginning. I have a full sun day today again and will watch throughout the day to see what time the 29.6V is being logged into the history. I will attempt to see if I can verify if this 29.6V is actually occurring or if the data stored in the log is somehow falsified.

In regards to the OVR Light, I have never had it activate for anything other than for 30A charge limiting previously until this firmware. With it being active at 26A it has to be activating for another reason and is likely due to this rogue high voltage reading.

I personally have very little experience with the U SET %. I understand it can be used in conjunction with a continuous DC power source to provide alternate charging options. My backup DC Generator creates a 28.8V charge which i send directly to the battery bank and do not run it through the kid so I have not attempted to use U SET % yet.

[RetiredTech]

Suits
I believe the voltage the OVR is monitoring is  the input voltage and alarms above 150V. I thought I read somewhere the OVR also reacts to over temperature which may occur when it's near it's limit. Could the V BATT MAX at 29.6 come from your backup generator spiking? The backup gen is across your battery bank so the V BAT MAX would register what is measured across the bank. Is it possible that the controller output spikes a bit when the controller is seeking it's MPP?

Brad

[suits]

My gas powered DC Generator is only connected to the batteries when in use, and I only use it from Nov - Feb when the sun does not provide enough power for my daily needs. I have no other devices or grid tie to my system. Only items connected to battery bank are the kid as well as the inverter. I operate 100% off grid so there should be no other devices affecting the voltage.

Your comments RE: Temperature monitoring via the OVR LED is interesting. I did notice the the unit felt slightly hotter to the touch than normal while the OVR light was on. I may devote further efforts to monitoring this as well.

I'm recording a chart now taking all readings every 15 minutes so I should have some clearer answers from that data by days end.

[ClassicCrazy]

I did find a small bug in the 30 day data logging that may be affecting you as well. On occasion it would only show today's data. When I scrolled to 1 DAY AGO it would show all values as zero's. This only happened once yesterday. I was able to get the history back by scrolling back to TODAY, then trying to go back to 1 DAY AGO again. The second time it showed the values ok.

Nope  - it just shows all zeros for me for logging other than today no matter what I try. I may hook up some panels to it today  and take it off constant voltage and see what it does.
Larry

[suits]

Nope  - it just shows all zeros for me for logging other than today no matter what I try. I may hook up some panels to it today  and take it off constant voltage and see what it does.
Larry

Then I would think you were spot on that its not able to detect the transition between days due to constant input power.

[suits]

Here's the results of this mornings testing. The VBATT Max value seems to begin to rise in conjunction with the Battery Voltage long before the OVR Led activates.

As soon as the OVR LED activates there's a significant and almost instant drop in current to 24.0A as well as battery voltage reported by the kid down to 28.0V. (Ohms law seems to go out the window at this stage with the values the kid is reporting) Also the batteries immediately began heavy gassing as soon as the led activated.

I'm going to take time to ponder the results, but you can find a chart of the data below.

Time	Charge Power	Charge Current	Kid Bat Voltage	VBATT Max	OVR Led State
8:53am	52W	2.1A	24.3V	25.2V	OFF
9:13am	61W	2.6A	24.3V	25.2V	OFF
9:32am	112W	4.6A	24.6V	25.2V	OFF
9:45am	145W	6.0A	25.0V	25.2V	OFF
10:10am	248W	9.7A	25.9V	26.3V	OFF
10:25am	339W	13.0A	26.3V	26.8V	OFF
10:31am	418W	15.9A	26.6V	27.2V	OFF
10:40am	540W	19.7A	27.1V	27.7V	OFF
10:46	640W	23.4A	27.4V	28.0V	OFF
10:56am	692W	25.1A	27.6V	28.5V	OFF
11:17am	841W	29.5A	28.6V	29.4V	OFF
11:27am	856W	29.9A	28.7V	29.6V	OFF
11:34am	772W	27.0A	28.8V	29.6V	ON
11:41am	681W	24.0A	28.5V	29.6V	ON
11:47am	686W	24.0A	28.7V	29.6V	ON
11:53am	692W	24.1A	28.9V	29.7V	OFF
12:17pm	532W	18.5A	28.8V	29.7V	OFF

[ClassicCrazy]

What charge state were those readings in ?  Would like to know if the controller was in Bulk, Absorb, Float  ?
Also are there any loads on the system at those times ?  Is the Charge Power and current you are reporting the input or Whizbang amps ?
Do you have a Whizbang on it ?
  And is the controller doing any temperature compensation ( batteries cold ?)
I will start paying attention to the Kid now- never really did because I had it plugged into constant voltage source. But now that I have it on PV I will try to figure out what it is doing and see if all that logging is working.

Larry

[suits]

What charge state were those readings in ?  Would like to know if the controller was in Bulk, Absorb, Float  ?

I would estimate SOC around 60-65% at the start of data collection. The controller was in Bulk up until it entered Absorb mode at the 11:17am reading or 17 mintues prior to the OVR Led becoming active

Also are there any loads on the system at those times ?  Is the Charge Power and current you are reporting the input or Whizbang amps ? Do you have a Whizbang on it ?

I had a consistent load of aprox 65W (laptop and fireplace fan), and a varying load from the fridge around 40W (after the initial 600W compressor motor starting load). All readings were taken at a time the fridge was not running to try and limit its impact on the data.

I do not have a Whizbang at the moment. The Charge Power and Current values are taken directly from the status screen of the kid. I did monitor battery voltage via multimeter as well as via my inverter display. No spikes were ever recorded at those two data points unless they were brief enough not to register on the equipment. I unfortunately don't have a DC current tester with a high enough current rating to verify current to the battery.

  And is the controller doing any temperature compensation ( batteries cold ?)

No temp compensation at this time. Room temperature where the batteries were stored was aprox 64F for the duration of the test while the exterior temps at panels aprox -25F

But now that I have it on PV I will try to figure out what it is doing and see if all that logging is working.

The VBATT Max value definitely seems to be over reporting. The fact that its not a consistent difference between what the kid status screen reports, and the VBATT Max logs, leads me to believe its not a minor firmware programming issue as I would expect that to be a little more consistent in how much it would be over reporting (Either a fixed 0.?V above the status screen or even a % of the reported value). The fact it seems to vary quite a bit between readings lead me to believe something else is the cause. But thats pure speculation on my part at this time.

[ClassicCrazy]

If it goes to Absorb at 28.8 it should hold that voltage steady until Absorb time is up - as long as there is enough current for the loads which it sounds like there is .
So not sure why your voltage is not steady .

And there is no reason for it to read high  unless for some reason it is reading the open circuit voltage instead of the battery voltage.

Larry

[ClassicCrazy]

This is a nice inexpensive DC clamp meter
http://www.ebay.com/itm/UNI-T-UT210E-Digital-Clamp-Meter-Multimeter-Handheld-RMS-AC-DC-Mini-Resistanc-/252445358891?hash=item3ac6ea7b2b:g:Q00AAOSwoydWj2id

Larry

[suits]

Much appreciated.

I think for the next troubleshooting step I'm going to split my system in half and then run two separate days of testing on each to compare the results.

Day 1 Test : 2x260W Panels + 2x6V Batteries (12V Config)
Day 2 Test : Other 2x260Panels + 2 Other 6v Batteries

I'll see if the absorb voltage variance and VBATT Max issue still occur under a 12V charge environment . This should also flag if any one panel, or one battery is somehow the cause of all this.

[ClassicCrazy]

what kind of batteries are they ?  Are they all the same kind and age ?

One way to tell is to feel them and see if one is getting warmer than the other.