A Forum run by Enthusiasts of MidNite Solar

Charge Controllers and Clippers => The "KID" charge controller => Topic started by: Steve_S on August 18, 2021, 02:34:27 PM

Title: KID with LiFEPO4, 660W-Panel & Inverter ?
Post by: Steve_S on August 18, 2021, 02:34:27 PM
Good Day folks,

I'm in process of building a "Tool Shed" of sorts.  It will have a small system as 120V is minimally required for occasional lights, possibly lawn tractor battery charging and light work stuff.  The TWO Solar Panels will be used as a sun-shade above the two doors, running wide for 12'.

System Config as follows:
MNKid SCC, BabyBox with 30A(panels), 30A(Battery)and 15A (24V Load).
Two Sillfab SIL-330 NL 330W 60 Cell Mono Panels is series.
1x, 24V/105AH LiFePo4 Battery Pack with JBD-150A Smart BMS & Heltec Active Capacitance Balancer.  *1
-- Inverter Options: (I have both, A) I have used and is good, the B) is New in box unused.
- Inverter-A:  Yiyen APC-3024 24V/3000W Low Frequency Inverter/Charger Hardwired to 120VAC Only.
- Inverter-B:  MasterCraft 12V/3000W High Frequency Inverter (no charger)
*1)  I can make it either 24V/105AH or 12V/210AH but am more inclined to 24V as my componentry is 24V everywhere else.
The inverter will be ON only when needed.  24V Load will be to LED Lights.

A BlueSea 9000 Series switch will be between inverter / battery as the battery has to be removable using an Anderson type connector.

I have looked at available docs, all good, nothing crazy or unexpected there.
SADLY, there are No Diagrams / Schemas showing KID's with Inverter's installed - We know people are doing it yet an obvious images to answer such questions are not handy.  Would seem like an obvious thing to include...   probably a pretty common use case too.

Now Gosh dang it, I happen to have 6 extra Deltec 500A/50mv shunts (New Old Stock) and no WinBangJr for the Kid... derp. 
Now another SPD to be gotten...   oivey.

Fortunately I have about 1 month before I get to the Toolshed power systems and then the finalization of my main solar system too, just in time for Winter LOL.

If anyone has diagrams or photo's of their MNKid with Inverter installation, I'd love to see them.
I'm sure others would as well.

Thanks in Advance,
Steve_S
Title: Re: KID with LiFEPO4, 660W-Panel & Inverter ?
Post by: Highflyer on August 29, 2021, 02:46:49 PM
Steve,

I have used KIDs in 12, 24 and 48 volts.  I have always used an inverter on my systems to "have" 110 AC power available.  I use two Deltecs in two separate enclosures (they were small), one for each lead. I used a fuse on the positive lead out of the battery for protection.  My inverters and Kid inputs were at the top of the Deltecs and the battery was on the bottom connection.  I used the WBJr on the negative lead for control and accurate SOC.  I'll go find a good picture of one of the setups, but it is really that simple.

Hope this helps.
Title: Re: KID with LiFEPO4, 660W-Panel & Inverter ?
Post by: Highflyer on August 29, 2021, 03:04:43 PM
Steve, 

I found this earlier picture of a test setup of the KID in 24v going to a 1500 watt samlex inverter.  We had this one up and running for a winter with no issues.  It went to a different location and has been rebuilt several times, all without issue.
Title: Re: KID with LiFEPO4, 660W-Panel & Inverter ?
Post by: Vic on August 29, 2021, 03:15:11 PM
In addition to what Brian has said;

Be certain that PV negative from the panels is connected to the PV negative terminal of the KID,  and that no other negative is connected to this terminal.

Do NOT connect the PV negative cable to the battery negative,  as the KID calculates its output current from the measuring the current that the PVs are delivering (it has a Low Side Shunt).

You could look at the wiring diagrams for the Classic,  just remembering,  that the Classic does not have a Load output,  and that the KID must have the PV negative lead connected separately to its PV Neg terminal,  and NOT to the battery negative.

FWIW,  Good Luck with your project,   Vic
Title: Re: KID with LiFEPO4, 660W-Panel & Inverter ?
Post by: Steve_S on August 30, 2021, 07:15:26 AM
Thanks for the responses guys.

The project took yet another twist of Evolution.  Some might say a Leap LOL. 
Kid -> 175A E-Panel, SPD etc. which takes care of the breakers and other stuff and allows me to Match my other system running the Classic 200 & Samlex EVO-4024.  I'll be taking advantage of the 24VDC-Load and running that to a 24V->12V converter for some low power stuff through a BlueSea 12V Panel. 

The First Battery Pack will be another DIY'ed 24V/105AH/2.68kWh LiFePO4 using EVE Matched Cells,
8pcs EVE-105AH Matched Cells:  ($398 USD)
https://szluyuan.en.alibaba.com/product/1600191337976-818333030/4pcs_EVE_105AH_LiFePO4_LFP_3_2V_Cells_Battery_Fully_Matched_Genuine_Grade_A.html?

1pc JBD Smart BMS Common-Port with BlueTooth module, Cold Temperature cutoff.  PART NUMBER: JBD-SP08S004 ($79 USD)
https://dgjbd.en.alibaba.com/search/product?SearchText=SP08S004

1 pc  HelTec Active Capacitance Balancer Model Number: 0877A ($25 USD)
Plus S&H
https://www.alibaba.com/product-detail/6S-7S-8S-5A-Lifepo4-Lithium_62357181825.html

I will document, diagram & photograph it for Posterity and post it here when I also update my other Build Info which is sorely outdated on here now.  That is a Midnite Classic-200, Samlex EVO-4024 and 5 LFP (LiFePO4) packs in one bank for 30.4kWh and 8 Rolls Surerete S-550's Heavy Lead in Bank 2 for a 22kWh Gross as secondary power (the bank I started with).  Somewhat different system than the usual but not that odd.

IF Anyone is interested in Building their own LFP Battery Pack or Bank, there is a How To Build your pack instructions posted here on this forum.  Link here:  http://midniteftp.com/forum/index.php?action=dlattach;topic=5143.0;attach=8402

Thanks for the feedback, Have a Great Day Everyone !
Steve_S
Title: Re: KID with LiFEPO4, 660W-Panel & Inverter ?
Post by: ClassicCrazy on August 30, 2021, 03:14:19 PM
Steve , have stuck with 24v because of existing inverters ?
I am tempted to make a lithium pack using your sources.

Larry
Title: Re: KID with LiFEPO4, 660W-Panel & Inverter ?
Post by: Steve_S on August 30, 2021, 05:19:47 PM
My main system is 24V and the one with the Kid is getting my 24V/3000W APC.  I do have a 12V/3000W HF "Car Type" Inverter but I'm not keen on it to be honest.

I 1st bought a prebuilt, what a freakin mistake that was 3k worth of lesson !  Then I discovered the world of building them and well, the rest is history.  A large amount of folks have used my instructions (it's even printed as a brochure now) and are happy campers having saved a pile of dough.  The thing is, having a known good reputable vendor, and Luyuan is one of those.  It is actually one of the reasons I gave that document to them as well, to help them help others and deliver even better service to the clients.  All I got was my name attached to it, cause that's all I wanted.  Opensource/freeware/shareware guy for life, LOL.  Knowledge is to be shared it's not a commodity.