Author Topic: How to connect Solar Charger And Shore Power(Grid-tie) Inverter Charger  (Read 347 times)

ColoradoELK

  • Newby
  • *
  • Posts: 2
Hi,

My question is  how do I connect the Midnight Classic 150 charger side in conjunction with a grid-tie battery charger?
Can I just hook them in parallel  or do I need isolation?

Sorry if this is already answered somewhere,  I've been searching the forum (and the manual) for the past couple hours and couldn't find this question elsewhere.

Details:
I am installing a solar system on my camper.   
I have an AIMS Power 4kW Inverter/charger (PICOGLF40W12V120V) and a 280aH LifePO4 battery bank (12V).
In addition to being an inverter, the AIMS unit will also charge the batteries when connected to shore power.

Now I want to install solar.  I bought a Midnight Classic 150 And Renogy 12V, 100W panels ( 5 in series).

Are there diagrams of such a connection somewhere that I've just overlooked?

Thanks for pointing me in the right direction!







ClassicCrazy

  • Hero Member
  • *****
  • Posts: 1445
This question was recently asked and some suggestions were made here
http://midniteftp.com/forum/index.php?topic=3744.0

though at the end this discussion strayed off topic about Classic Voice - the beginning is on topic .

Larry
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , 16s Calb 100AH LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batterie

Vic

  • Hero Member
  • *****
  • Posts: 1771
Hi ColoradoELK,

The photos in the Post that CC Larry linked are very clear.

You DO want a DC-rated breaker on the Classic  PV input,  and on the Classic output connection to the battery.

Breakers are sized to protect the cable that connect to the breakers.  Most of us use Building wire for this,   usually THHN type that uses 19 strands of wire in each cable run.

That AIMS inverter is very LARGE for a 12 volt system.  Please make certain that there are adequately sized cables for the inverter connection,   and battery interconnects,  to match the size of the circuit protection (breaker or fuse) on the inverter DC battery cables.

Also,  it is possible that that inverter might not have the capability to charge Lithium batteries correctly.   I am no expert on Li batteries,  but CC Larry certainly is.

FWIW,   Vic
Off Grid - Two systems -- 4 SW+ 5548s, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 3X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  Thanks MN for Great Products/Service/Support!

ClassicCrazy

  • Hero Member
  • *****
  • Posts: 1445
This is what the owners manual for that inverter says

http://www.aimscorp.net/documents/PICOGLF40W12V120V.pdf

Automatic Neutral-to-Ground Connection
All single phase 120Vac
inverters are equipped with automatic neutral-to-ground switching.
These inverters use an internal relay that automatically
connects the AC neutral output to the vehicle/boat’s
safety ground(“bonding”it)in Inverter Mode
and disconnects it (“un-bonding” it) when they have connected to
a qualified external AC source.
This design avoids two neutral-to ground connections from
existing at the same time, thereby preventing an
electrical shock hazard between the vehicle/boat’s neutral and the external AC source’s neutral
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , 16s Calb 100AH LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batterie

ColoradoELK

  • Newby
  • *
  • Posts: 2
Thanks for the responses.  I'll check them out.......

OK.  That is good to know about the grounding.  Seems I did it right.

But actually I was referring to the two chargers possible fighting each other....

I guess to rephrase the question...  Say I have shore power available and plug in.. In that case the AIMS inverter/charger,  wants to start charging the batteries.   Will I damage the Midnight Classic? 

Can I just hook both chargers to the batteries?  ( I will have the recommended DC Breakers of course).

Thanks again.
« Last Edit: June 24, 2017, 01:13:28 AM by ColoradoELK »

ClassicCrazy

  • Hero Member
  • *****
  • Posts: 1445
I think the grounding issues  is in relation to the AC side of things.
But I could be missing something because I haven't studied up on wiring for RV/Boats .
Larry
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , 16s Calb 100AH LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batterie

bee88man

  • Newby
  • *
  • Posts: 14
With having breakers mentioned you may switch off whichever one charger is not being used at the time..

tecnodave

  • Hero Member
  • *****
  • Posts: 615
  • Learn something new every day
Hi Colorao ELP....

It should not be a problem having more than one DC source to charge the battery bank. It will not hurt the Classic to have another source to charge the batteries. If the AIMS inverter has a higher charge voltage than the Classic then the Classic will think it's seeing a fully charged battery and go to float mode. Same if the Classic has the higher voltage....the AIMS will be  "seeing" a fully charged battery and stop charging. Getting these two sources to share will be only a problem with "tweeking" the set points in the Classic AND the AIMS inverter (if it is adjustable). They should not be damage each other in this configuration....

David
#1 Classic 150 12 x Sharp NE-170, 2S6P, 24volt L-16 Rolls-Surette S-530, MS4024 & Cotek ,  C-40 dirv.cont. for hot water
#2 Classic 150 12 x Sharp NE-170, 2S6P, 24 volt L-16 Interstate,Brutus Inv.
#3 Kid/WBjr 2 Suntech 280 24v AGM 105 a.h. Exeltech Inv.
#4 Kid/WBjr 2 Suntech 280 12v AGM 105 a.h.