Cruisers Forum
 


Join CruisersForum Today

Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 09-01-2020, 09:35   #1
Registered User
 
Santiano's Avatar

Join Date: Aug 2019
Location: San Francisco, USA
Boat: Pearson 323
Posts: 61
Just installed LiFePO4 and solar array not working/going crazy.

Hey CF,

I was up til 0400 today installing my new battery bank, and solar array. Nothing is working as expected, so I was hoping I could glean some help from you all. 3 issues:

- The battery cells are 100ah 3.2v arranged in 2p4s to make a 12.8v 200ah system. They arrived a couple of weeks ago and I immediately tested them with the multimeter. 3.29 volts per cell. And 13.16 when connected in 2p4s. So far so good, I thought. Hook them up last night and the total voltage reads 13.05 volts on both my $20 battery monitor screen and on the victron MPPT. But multimeter shows 3.29 volts per cell and 13.15 total. Multimeter is just garbage, then, I guess?

- I hooked up my circuit following the attached diagram, except I ran the negative lead on the battery to ground on the engine block. That's what I had done with my lead acids before and it worked fine. This time I get voltage readings from the monitor and the MPPT, but no power to the house. Might be a bad connection somewhere, I guess. Any thoughts as to troubleshooting this?

- Finally, I wake up this morning hoping that at least the victron charger is working well, and I see the voltage/amperage graph attached. Amps are 0 and voltage seems to be oscillating between about 15 and 35 volts! What on Earth have I done?

Anyway, I'm totally exhausted. Going to try to catch a few more hours of sleep and then get back to it. Hoping to get the kinks worked out today, and that I haven't done anything seriously damaging to all this.

Sincerely.
Attached Thumbnails
Click image for larger version

Name:	lifepo4_22.jpg
Views:	170
Size:	66.7 KB
ID:	206620   Click image for larger version

Name:	Screenshot_20200109-080556.png
Views:	111
Size:	85.1 KB
ID:	206621  

__________________

Santiano is offline   Reply With Quote
Old 09-01-2020, 15:38   #2
Registered User
 
Santiano's Avatar

Join Date: Aug 2019
Location: San Francisco, USA
Boat: Pearson 323
Posts: 61
Re: Just installed LiFePO4 and solar array not working/going crazy.

Well, this was a bit of bleary panic post after an exhausting night of wiring. I woke up refreshed and managed to sort most of it out. Cheers.
__________________

Santiano is offline   Reply With Quote
Old 09-01-2020, 16:03   #3
Registered User

Join Date: Sep 2018
Location: Vancouver B.C. Canada
Boat: Prout Quasar 50
Posts: 52
Re: Just installed LiFePO4 and solar array not working/going crazy.

Quote:
Originally Posted by Santiano View Post
Well, this was a bit of bleary panic post after an exhausting night of wiring. I woke up refreshed and managed to sort most of it out. Cheers.
Do you mind sharing what the problem was for the benefit of others
__________________
Prout Quasar 50
madprops is offline   Reply With Quote
Old 09-01-2020, 16:09   #4
Registered User
 
Santiano's Avatar

Join Date: Aug 2019
Location: San Francisco, USA
Boat: Pearson 323
Posts: 61
Re: Just installed LiFePO4 and solar array not working/going crazy.

The Victron MPPT stabilized its voltage readings around 40 by the time the sun was high. That is a problem I'll have to address if it recurs, but for the moment I'm just glad it's looking good.

The general problem with the circuit was a bad fuse or fuse holder, haven't worked out which yet. But that's solved.

I'm still getting different readings from different instruments, but chalking that up the the variety of cheap Chinese monitors and multimeters and balancers I have currently. Gonna have to shell out for a nice(er) multimeter soon.
Santiano is offline   Reply With Quote
Old 09-01-2020, 17:10   #5
Registered User

Join Date: Feb 2015
Posts: 847
Images: 1
Re: Just installed LiFePO4 and solar array not working/going crazy.

I think the issue is that the Victron display is reporting the solar array voltage which is and will be very different from the battery voltage.

The swings you saw were just the solar controller testing to see if the panels could deliver any useful power.

You need to look at the MPPT output, not the input.
__________________
www.MVTanglewood.com
tanglewood is offline   Reply With Quote
Old 09-01-2020, 17:29   #6
Registered User
 
Santiano's Avatar

Join Date: Aug 2019
Location: San Francisco, USA
Boat: Pearson 323
Posts: 61
Re: Just installed LiFePO4 and solar array not working/going crazy.

Oh, I was definitely not under the impression that my battery voltage was swinging between 15 and 40 volts. But on the other hand, I do not know how solar controllers work - this is my first experience with one. I hope you are correct and it was just a test mode of the mppt.

Anyway, the mppt still shows the battery voltage at 13.55 at the same time as both my other monitors show it at 13.25. still a bit disconcerting.
Santiano is offline   Reply With Quote
Old 10-01-2020, 10:55   #7
Registered User

Join Date: Mar 2015
Posts: 498
Re: Just installed LiFePO4 and solar array not working/going crazy.

Quote:
Originally Posted by Santiano View Post
Oh, I was definitely not under the impression that my battery voltage was swinging between 15 and 40 volts. But on the other hand, I do not know how solar controllers work - this is my first experience with one. I hope you are correct and it was just a test mode of the mppt.

Anyway, the mppt still shows the battery voltage at 13.55 at the same time as both my other monitors show it at 13.25. still a bit disconcerting.
Are all devices measuring from exactly the same point?
.25 volt seems like a lot of difference even for cheap meters.
I suggest checking each connection with volt meter looking for a high resistance point.
guyrj33 is offline   Reply With Quote
Old 10-01-2020, 16:12   #8
Registered User

Join Date: May 2008
Location: Currently cruising the eastern Caribbean
Boat: Lagoon 42, Minx
Posts: 168
Re: Just installed LiFePO4 and solar array not working/going crazy.

While it may seem like a lot of work, use another battery unconnected to anything, to check you instruments. I pulled out my car battery and making sure that all the instruments to be check are isolated, I found quite a bit of variation in voltage readings between instruments. The real trick is finding out which instrument was accurate.
singlespeed is offline   Reply With Quote
Old 11-01-2020, 07:04   #9
Sponsoring Vendor
 
YANDINA's Avatar

Community Sponsor

Join Date: Nov 2019
Location: South Carolina
Boat: Philip Rhodes Custom 71'
Posts: 91
Re: Just installed LiFePO4 and solar array not working/going crazy.

If a BMS system is disconnecting and reconnecting due to over voltage it would look like there were wild voltage swings on the battery.
__________________
Ann-Marie Foster
YANDINA
YANDINA is offline   Reply With Quote
Old 12-01-2020, 01:44   #10
Registered User
 
Cpt Pat's Avatar

Join Date: Feb 2012
Location: Half Moon Bay, CA, USA
Boat: 1963 Pearson Ariel, Hull 75
Posts: 1,069
Re: Just installed LiFePO4 and solar array not working/going crazy.

Quote:
Originally Posted by Santiano View Post
The general problem with the circuit was a bad fuse or fuse holder, haven't worked out which yet.
I'm not sure which type of fuse holder you have, but beware of the twist-together type. (See photo.) They are not water tight, are constructed of POS (Plain Old Steel) that rusts and worst of all, the connection is held by an internal spring -- if enough tension is placed on the wires, the connection with the fuse will pull apart internally breaking the connection. The connection will re-make when the tension is released. That can make you crazy if the problem is intermittent, like in a wiring bundle that moves at sea.

The fuse holder below will corrode and fail in a very short time in a seawater/salt air environment. They also tend to melt before the fuse blows. They have no place on a boat. Their only redeeming quality is that they are dirt cheap.

For low current point-to-point wiring, I prefer the watertight ATO/ATC type fuse holders.
Attached Thumbnails
Click image for larger version

Name:	fuse.PNG
Views:	35
Size:	392.2 KB
ID:	206752  
Cpt Pat is offline   Reply With Quote
Old 12-01-2020, 03:44   #11
Moderator
 
noelex 77's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Boat: Bestevaer.
Posts: 12,068
Re: Just installed LiFePO4 and solar array not working/going crazy.

Quote:
Originally Posted by Santiano View Post
Oh, I was definitely not under the impression that my battery voltage was swinging between 15 and 40 volts. But on the other hand, I do not know how solar controllers work - this is my first experience with one. I hope you are correct and it was just a test mode of the mppt.
Yes Tanglewood, is correct (everything he posts is worth reading carefully). Your graph is displaying solar voltage not battery voltage.

You can see here in the first photo that solar voltage is selected on my system. In the second photo battery voltage is selected (it is almost a straight line). If you want, you can display two parameters on the graph, or even alter the time scale. In the third photo both battery voltage and solar voltage are shown:
Attached Thumbnails
Click image for larger version

Name:	BBE76478-F1DC-4215-9F3E-68C3DED74392.jpg
Views:	42
Size:	182.1 KB
ID:	206755   Click image for larger version

Name:	D54C9014-B0D8-470A-BE07-3D83F299BD4F.jpg
Views:	41
Size:	119.5 KB
ID:	206756  

Click image for larger version

Name:	12CC1F2B-3FD0-419D-B3B7-F8594AC33252.jpg
Views:	40
Size:	195.9 KB
ID:	206758  
__________________

noelex 77 is offline   Reply With Quote
Reply

Tags
lifepo4, solar, work

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
buying a 50' Alden Teak Deck. Crazy or insanely crazy? blunderbuss Dollars & Cents 30 11-06-2019 07:24
Best Solar Array's and Chargers? Divedoug68 Electrical: Batteries, Generators & Solar 12 04-11-2016 06:18
AC72....Crazy Cool and Cool Crazy Ocean Girl General Sailing Forum 6 30-08-2013 05:22
I Just Quit Smoking! I May Be Going Crazy Rocketman Health, Safety & Related Gear 43 08-11-2012 14:26
Just installed 1 Kyocera 245 watt solar panel Panamajames Electrical: Batteries, Generators & Solar 5 04-06-2012 17:29

Advertise Here


All times are GMT -7. The time now is 21:14.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.