Victron 150/85 is failing

[Katie33kate]

I have 690W on the roof handled by the victron 150/85. I have a 400amp 12v LiFePo4 battery. I’ve had this MPPT for 18 months. (since January of 2021). it has started to fail to charge my batteries up. Even in the winter, I would be back up to full by mid day. Now I am in high summer and cannot get the batteries charged up because the MPPT stops charging. (I am in the desert of New Mexico…endless sunshine).

at dawn (6 am) the MPPT kicks into bulk…this lasts about 1 hour, then drops to absorb. But this lasts for just a couple hours when the MPPT is showing 14.2 on the battery and it drops out into float. BUT…a battery monitor shows that I never get above 13.23 13.24. The monitor also shows I am at 72% when the MPPT is claiming 14.2. I have checked this with the volt meter at the battery…and the monitor is showing correct. Even after hours of drawing power for refrigerator, freezer, and swamp coole…the MPPT will not kick back to bulk. I have been down to 12.8 as measured by the volt meter…but the MPPT will not return to charge..

i tested the battery…used the inverter/charger to take it up to 14.2..then shut everything off. Tested the battery every hour for 24 hours. Of course the battery drops down to about 13.5. Then holds stead. Does not lose charge.

so…my problem is that Victron does not handle the sales/support/ etc themselves…and the seller on Amazon,( Inverter R Us) probably doesn’t actually know anything…but is blowing me off. Run this test..run that test….always with long delays between communications. If I ask a question is take a couple days before anyone gets back to me and then never answers my question….just round and round in circles. I have been forced to stay at an RV park on their electric. Meanwhile I an just getting the run around. It has been a month since the first phone call seeking support.

if, in fact, I do not understand what is happening with the MPPT…please help me understand. If I got this right and the MPPT if failing…what do you recommend to handle this seller? This cost ~$800.
thank you

 

[John Frum]

The monitor also shows I am at 72% when the MPPT is claiming 14.2.

When the SCC thinks the voltage is 14.2 volts test the voltage at the SCC system side.
What does your reference meter say?

What is the bulk voltage set to?
What is the absorption voltage set to?
Are you using an absorption timer or tail current or a combination?
What is the float voltage set to?
What is the re-bulk voltage set to?

 

[John Frum]

With the solar panels disconnected do the same measurment and see if the solar charge controller and the reference meter agree.

 

[rmaddy]

I'm not positive about this but I thought you could contact any Victron dealer to get support. It doesn't have to be the one you purchased from.

Worse case, if you need a new charge controller, keep in mind that with only 690W of panels on a 12V system you don't need 85A of charge current. The 150/45 would be plenty big enough. So it would be about $382 for a new 150/45 versus $697 for the 150/85.

 

[John Frum]

How are the panels configured?

 

[Katie33kate]

When the SCC thinks the voltage is 14.2 volts test the voltage at the SCC system side.
What does your reference meter say?

What is the bulk voltage set to?
What is the absorption voltage set to?
Are you using an absorption timer or tail current or a combination?
What is the float voltage set to?
What is the re-bulk voltage set to?

Sorry…what is SCC?
the settings are all the default LiFePo4 preset on the switch on the face of the MPPT….rotary setting 7. This is preset by victron. I have never messed with the user defined settings……

let me say this….this is my 3rd victron on this system. I added a second one for the portable panels which I no longer have. This one replaced the smaller one…in prep for the day I get 2 425w panels.

 

[Katie33kate]

With the solar panels disconnected do the same measurment and see if the solar charge controller and the reference meter agree.

They do. With panels off….the MPPT says battery 13.23. The volt meter reads 13.23.

 

[Katie33kate]

I'm not positive about this but I thought you could contact any Victron dealer to get support. It doesn't have to be the one you purchased from.

Worse case, if you need a new charge controller, keep in mind that with only 690W of panels on a 12V system you don't need 85A of charge current. The 150/45 would be plenty big enough. So it would be about $382 for a new 150/45 versus $697 for the 150/85.

Victron says the seller is responsible.

 

[rmaddy]

what is SCC?

solar charge controller

Commonly used Forum Acronyms & Abbreviations

Solar is befuddling enough! Why use acronyms? Well, we're lazy typists.... :LOL: xSyP - e.g., 2S2P, shorthand for how many cells in Series (S) and Parallel (P). A - Amperes or amps. A measure of current. See warning. AC - Air Conditioning, sometimes A/C. AC - Alternating Current, a waveform...

diysolarforum.com

 

[Katie33kate]

How are the panels configured?

They are 2 panels…wired in parallel. That hasn’t changed in 5 years.

 

[Katie33kate]

solar charge controller

Commonly used Forum Acronyms & Abbreviations

Solar is befuddling enough! Why use acronyms? Well, we're lazy typists.... :LOL: xSyP - e.g., 2S2P, shorthand for how many cells in Series (S) and Parallel (P). A - Amperes or amps. A measure of current. See warning. AC - Air Conditioning, sometimes A/C. AC - Alternating Current, a waveform...

diysolarforum.com

So..you are asking me to test with a volt meter the battery side of the SSC…and the Panel side of the SSC?
that would be interesting….I would expect a volt meter at the battery and a volt meter on the battery side of the MPPT to be the same…. I’ll set up that test tomorrow. For right now I have the inverter/charger bringing my battery back up.

 

[Katie33kate]

When the SCC thinks the voltage is 14.2 volts test the voltage at the SCC system side.
What does your reference meter say?

What is the bulk voltage set to?
What is the absorption voltage set to?
Are you using an absorption timer or tail current or a combination?
What is the float voltage set to?
What is the re-bulk voltage set to?

Also….the moment in time when the SCC thinks voltage is 14.2. Charging stops, and the battery settles rapidly to 13.5 (full). Catching it at 14.1 is a longer time as that is still in absorb. I’ll try this tomorrow morning. This afternoon I have to use park electric to get the batteries up or I cannot get thru the night.

 

[Pim57]

Good chance that the wiring between the Victron and the battery has gone bad. Meaning got more restistance, loose, broken, corroded, rodents or ….

This would create an extra voltage drop where the voltage at the Victron is 14.2 and the voltage at the battery terminals is 13.5.

The Victron seems to be Okay because it starts with bulk, then absorption and finally ends in float. It’s all about the voltage that’s somehow wrong.

 

[Katie33kate]

Good chance that the wiring between the Victron and the battery has gone bad. Meaning got more restistance, loose, broken, corroded, rodents or ….

This would create an extra voltage drop where the voltage at the Victron is 14.2 and the voltage at the battery terminals is 13.5.

The Victron seems to be Okay because it starts with bulk, then absorption and finally ends in float. It’s all about the voltage that’s somehow wrong.

Interesting idea. It will show up when I test the MPPT side In the morning.

 

[HOU_Castle]

Interesting idea. It will show up when I test the MPPT side In the morning.

After all of the testing, please disconnect and reconnect the wirings. It happened to me before. Hope this will work.

 

[John Frum]

@Katie33kate I'm guessing you will hit absorption in ~30 minutes.
As soon as you hit absorption please measure the voltage and the SCC output terminals.
I want to see if the SCC and your multi-meter agree on the voltage at the SCC output terminals.
Also check the voltage at the battery terminals.


Please provide a product link to your exact charge controller.

Solar Charge Controllers - Victron Energy

Get the highest attainable efficiency from sunlight, even if it is limited, with the solar charge controllers from Victron Energy. Find a dealer nearby.

www.victronenergy.com

Also pictures of the core of your system including batteries, main busbars and solar charge controller would be awesome.

 

[Katie33kate]

Ok…so..I measured the voltage (with volt meter) at the MPPT. It read 14.12. (Absorb). I measured the voltage at the buss bar….it read 13.2. Yep…so..I went from the buss bar toward the MPPT….there is a 80amp fuse. Measured each side of the fuse…..yep..that is where the voltage drop is happening. Wow..thank you!

so, I turned off the whole system and disconnected the cable (4 gauge) and I found a partly melted fuse holder!!!!!!

oh wow

the fuse didn’t blow, but the melting warped the shape and I had a bad time getting the whole thing out. It twisted the prongs in the fuse too.

why did t the fuse blow? Hey, I’m sort of glad it didn’t cause it would fry the MPPT….but, concerned that a fire could have happened. Which makes me wonder…how did it happen? By my calculations there isnt anyway that MPPT with those solar panels could have gotten above 60amps.

so, I think I need a better quality fuse holder. I got this one from Amazon a long time ago….maybe there is a manufacturer that is known for being the best?

again..thank you folks for solving this.

smoothjoey….wow, I can post pictures…but it is a rats nest. It sort of grew. As i learned more, I added more….all inside a skinny cabinet. You can see what I mean …this pic is just one side. but…here is a drawing of the system

since that drawing was made…I separated out the MPPT on its own buss bar because I added a second MPPT and a wind charge controller. So, I basically have one buss bar for all those items that discharge the battery.…and a second buss bar for all those items that charge the battery. I also added a 3rd 12v fuse block for the outside 12v outlets (usb-c and Anderson)….

 

[rmaddy]

why did t the fuse blow?

The fuse didn't blow because you didn't have too many amps. You probably have/had a bad crimp or connection that is causing excessive heat and the heat is causing issues. The bad crimp/connection is causing the voltage drop and the heat. Triple check all of your crimps and connections. Make sure everything is tight. Then measure everything for excessive voltage drop. If you have one of those infrared thermometers, check for anything getting too hot.

Hey, I’m sort of glad it didn’t cause it would fry the MPPT

Why would the SCC get fried if the fuse blows? That's not true at all. If the SCC loses battery power for any reason, it will not get fried just because the solar is still connected. Though I would turn off the PV disconnect before you restore battery power to the SCC, then turn the PV disconnect back on.

I think I need a better quality fuse holder.

And fuse. Look for Littlefuse brand or Bussman brand fuses and breakers. Blue Sea Systems is also a good one (I think their stuff is rebranded Bussman).

 

[HOU_Castle]

Ok…so..I measured the voltage (with volt meter) at the MPPT. It read 14.12. (Absorb). I measured the voltage at the buss bar….it read 13.2. Yep…so..I went from the buss bar toward the MPPT….there is a 80amp fuse. Measured each side of the fuse…..yep..that is where the voltage drop is happening. Wow..thank you!

so, I turned off the whole system and disconnected the cable (4 gauge) and I found a partly melted fuse holder!!!!!!

oh wow

the fuse didn’t blow, but the melting warped the shape and I had a bad time getting the whole thing out. It twisted the prongs in the fuse too.

why did t the fuse blow? Hey, I’m sort of glad it didn’t cause it would fry the MPPT….but, concerned that a fire could have happened. Which makes me wonder…how did it happen? By my calculations there isnt anyway that MPPT with those solar panels could have gotten above 60amps.

so, I think I need a better quality fuse holder. I got this one from Amazon a long time ago….maybe there is a manufacturer that is known for being the best?

again..thank you folks for solving this.

smoothjoey….wow, I can post pictures…but it is a rats nest. It sort of grew. As i learned more, I added more….all inside a skinny cabinet. You can see what I mean …this pic is just one side. but…here is a drawing of the system

since that drawing was made…I separated out the MPPT on its own buss bar because I added a second MPPT and a wind charge controller. So, I basically have one buss bar for all those items that discharge the battery.…and a second buss bar for all those items that charge the battery. I also added a 3rd 12v fuse block for the outside 12v outlets (usb-c and Anderson)….

Cheap fuse or fuse holder will cause many issues in the future (including damaging to your eqpt). please get a good quality one. This is crucial. Glad that you found the issue.