Kid not charging, staying in rest mode

Started by earthworm77, December 07, 2019, 05:41:40 PM

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earthworm77

I have a small 12v solar array for my off grid cabin which I visit 3 or 4 times a year. It consists of 4 150w Renogy panels connected to my Kid which in turn sends DC to a pair of NPP NPD12-200Ah 12V 200Ah 4D Deep Cycle Wind Solar SLA Batteries. The current then goes to a Samlex 2000W inverter. I've run this system for about 4yrs with zero issues.

This week I noticed the readout on the Kid was in Rest mode w/ 0watts incoming from the panels. I chalked it up to cloudy weather. The batteries were at 12.7V so it was around normal...usually it reads 13.1V or so when the sun is out for any length of time. I have a fuse on the positive lead from the panels into the Kid and one on the output to the batteries. Both 20A fuses.

I've never had any issue before. It has all worked consistently until I noticed it this week. Today, I checked the configuration of the panels, swapped out the MC4 connectors, rewired everything to the Kid, checked the fuses, made sure all the connections to the Kid were solid.......no change.....0w.

I do think toggling modes seemed delayed so I am thinking the issue is with the unit. My knowledge of electricity is pretty basic and only allowed me to set this thing up and have it work. Any advice on what is going on here?

ClassicCrazy

It would really help to get a digital multimeter and learn the basics on how to use it to do basics on how to diagnose the system. Such as battery voltages, PV voltages, and checking other voltages around the system or continuity tests for fuses  where needed .
If you do have  meter it would help to know what voltages you have checked.  Hard to guess what might be going on with your system.

Larry

system 1
Classic 150 , 5s3p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system 2
 5s 135w Kyocero , 3s3p 270w Kyocera  to Classic 150 ,   8s Kyocera 225w to Hawkes Bay Jakiper 48v 15kwh LiFePO4 , Outback VFX 3648 inverter
system 3
KID / Brat portable

boB


Yes, what is the PV input voltage of the kid during the day ?   It would have to be somewhat higher than the battery voltage in order to start up charging and come out of resting.

Are the 4 panels in series ?  That should take the Kid's input voltage plenty high enough to start I would think ?




K7IQ 🌛  He/She/Me

Nomad1

I observed exactly the same problem last winter and initially thought it was caused by shitty weather. After a few months in 0w mode KID turned off with awful smell and leaked capacitor electrolyte. I sent it for repair, Midnight Europe guys replaced the motherboard and for last 9 months it has been working like a clock.
Programmer

earthworm77

Quote from: ClassicCrazy on December 07, 2019, 10:30:47 PM
It would really help to get a digital multimeter and learn the basics on how to use it to do basics on how to diagnose the system. Such as battery voltages, PV voltages, and checking other voltages around the system or continuity tests for fuses  where needed .
If you do have  meter it would help to know what voltages you have checked.  Hard to guess what might be going on with your system.

Larry

Absolutely, if I had one with me at the time, I would have done that first. I unfortunately had to go back to Florida and won't be in NC until March. I'll bring a cheap charge controller with me just to use until I get this figured out. If I test the unit with a multi meter and the current from the panels is good up to the unit, I'll know the unit has an issue and will send it for repair.

earthworm77

Quote from: Nomad1 on December 09, 2019, 04:24:00 AM
I observed exactly the same problem last winter and initially thought it was caused by shitty weather. After a few months in 0w mode KID turned off with awful smell and leaked capacitor electrolyte. I sent it for repair, Midnight Europe guys replaced the motherboard and for last 9 months it has been working like a clock.

At this point I am kind of going with this as I am convinced it is the unit and not any other influence.

KyleM

earthworm77   

The "Magic formula"  is that the KID needs to have 130% of battery bank voltage in order to START charging.
That does not mean you will get peak output  that is just  to get things started.

So on a 12 volt system  you would need 15.6 volts coming from the array  just to start charging.
That is 15.6 volts all the way to the inside of the KID.   I like to hedge my bets and try to keep my voltage over 18 volts at the terminal block
(that is where the wire connects from the PV to the KID)  that way there is a little bit of over in case there is a small connection problem.

There are a few places that the Voltage can see a drop due to bad connections on the KID: the terminal block - the Fuse in the face of the KID and other internal components.

If you are just barely over the minimum volts you will see the KID in resting mode or bulk mppt or even see bulk mode but not processing any watts.


This is why having a good voltmeter on hand is so critical. By taking a reading at the terminal block we can estimate what is going on deeper in the KID.

If you are seeing 14 volts at the terminal block there is no way the KID will be able to charge a 12 volt system, there is just not enough power getting through.
Then we are looking at configuration changes wiring issues on the PV side or just waiting for better sun.

If you are getting 30 volts at the terminal block but the KID is in resting mode, then there is something in the KID not letting that power get to where it needs to be.

That is when it is time to send it in for repair. 

* NOTE   -  Replace the fuse in the face of the KID with a standard 40 amp fuse before you send it in. Even if it looks new.
We get many KIDs back here that we replace the fuse and it suddenly starts working. That goes from a .25 cent fix to a $40.00 fix and a week without your charge controller.

I hope this helps you understand the Midnite KID a little better.


-Kyle

earthworm77

Thanks Kyle, I'll give it a shot with new fuses when I get back up there in a couple of months.
Maybe the actual issue was the lack of sun as it was pretty cloudy all week. I thought I did get a day where the sun came out enough that the system should have been working as normal. I should have checked it with a volt meter.


Is there any way I could purchase another owners manual for my Kid?

ClassicCrazy

Quote from: earthworm77 on December 17, 2019, 10:58:10 PM
Thanks Kyle, I'll give it a shot with new fuses when I get back up there in a couple of months.
Maybe the actual issue was the lack of sun as it was pretty cloudy all week. I thought I did get a day where the sun came out enough that the system should have been working as normal. I should have checked it with a volt meter.


Is there any way I could purchase another owners manual for my Kid?
You can download owners manual from midnite site .
http://www.midnitesolar.com/documents.php?productCat_ID=43&productCatName=Charge+Controllers+-+KID&model=MNKID-B&product_ID=530&act=

Larry
system 1
Classic 150 , 5s3p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system 2
 5s 135w Kyocero , 3s3p 270w Kyocera  to Classic 150 ,   8s Kyocera 225w to Hawkes Bay Jakiper 48v 15kwh LiFePO4 , Outback VFX 3648 inverter
system 3
KID / Brat portable

earthworm77


ova

#10
Hello, thought I'd jump in here as I'm having the exact same problem: just bought a used KID, hooked it up. Receiving around 19V (tested at input terminal inside KID) from a 100W panel, it appears to be enough to switch the KID on and it gets 1W/.2A for about 1 second then shuts off, then turns back on and immediately shuts back off repeatedly. This should be enough incoming to keep it on but not happening. I've the latest firmware, have switched the fuses in the front and have reset to defaults and tried the three different solar input modes, battery bank voltage is 12.45. occasionally it will flash "bulk mppt" before going back to resting... i found my way into the diagnostic readout screen and the number in the lower right increases from 0 to over a thousand before resetting and making the clicking sound going back to rest/0, don't know what it is. i'm seeing that it's giving code 9 for last reason for resting "ReasonForResting=9 (IbattDisplaySi < -15) (negative current) (MB 4200)", i'm getting voltage across the battery positive and negative terminals inside the KID with it totally disconnected from battery.. if i probe from PV-in-positive to battery-out-positive i get 19V (incoming PV voltage), this does not seem right.. some kind of internal bleed between PV and battery inputs? Any ideas?... thank you

ClassicCrazy

Are your PV negative and Battery negative wires isolated from each other ? They can't be bonded together . Not sure if that is how you have them or if it would cause what you are seeing .


Larry
system 1
Classic 150 , 5s3p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system 2
 5s 135w Kyocero , 3s3p 270w Kyocera  to Classic 150 ,   8s Kyocera 225w to Hawkes Bay Jakiper 48v 15kwh LiFePO4 , Outback VFX 3648 inverter
system 3
KID / Brat portable

ova

#12
Thanks for the reply Larry,
PV negative coming straight from panel, not touching anything else. and battery negative going straight to battery. if they were intertwined, i'd expect weird results. but with all fuses out of the KID and the KID totally disconnected from the battery, I see voltage {19V from panel} when probing PV positive & battery negative terminals inside KID....

I received a reply from Midnite today just saying to add another panel, so I will try that today at some point.

Edit: I added a panel and the KID is running fine, guess it was just low voltage issue, anyway, problem solved. thanks for anyone reading and sorry to highjack the thread.