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Renogy system is still not working

Jules Pieter

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Joined
Feb 1, 2021
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6
Hello,


My campervan is almost finished but the Renogy system is still not working. I contact two campervan specialists (I payed them more than 1000 euro already) and I purchaed for a couple off thousand Renogy stuff. So you are asking me if I m satisfied? No not at all. So I hope you can help me ?


We bought this:


- 5 renogy solar panels (see correspondence benead, and atachemend)

- MPPT Laderegler 12V/24V 40A Rover Li

- BT 1​

- Batterie-Ladegerät DC zu DC 12V 40A

- LITHIUM LIFEPO4 BATTERIE 12V 100AH SMART BMS​

What happens?

After installing on May 21, the battery was at 80%. .25-05 on 76% What was striking is that it does not really charge on the solar panels (see the photos of the BT app). I then plugged in a vacuum cleaner and then it went to 66%. 26-05 he was suddenly at 4% percent and within an hour at 0%. (How can he go from 66% to 0% in less than 24 hours without anything heavy on? Same evening 2 hours on the charger and was back at 87% in the evening (how can he go from 0 to 87% in less than 2 hours?) Next morning at 78% (10% less without actually turning on). This morning he got up at 60% shortly after that he went to 0 and overdischarched although it didn't turn on. drove another specialist where I already had an appointment, then briefly turned on the engine and suddenly it got back to 76%.


The specialist (B & S in Hoorn, builds a lot of campers with Victron stuff) has checked the installation: everything seems to be connected properly. There is also little to no power leakage (same as they install it).


He only wonders whether the solar panels can be connected in this way (1 strand of 3 and 1 of 2). Are you sure this is possible as you confirm below?



If so, does it not charge on the solar panels? (Not even with other batteries, 40 volts but almost no ampere also on a sunny day, is 40 volts logical? ).


The bms doesn't seem stabel.

Regards,

Jules


How can we solve this?



Regards,
 

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How do you have those 5 panels wired to get 36v from your array? 3 in series and 2 in series, connected in parallel?
You should try this with 1 panel so you only have a couple connections to verify that your charger will charge.
A screenshot of your charge settings would be helpful.
Your diagram shows 2 x 12v batteries in series for 24v (and you do not mention your nominal battery voltage).
 
If your system is 24V then your problem is the Renogy batteries can not be connected series:
  • DO NOT string the battery in series. It is made ONLY for 12V parallel connections using the batteries of the same manufacturer and model.
 
Thanks for your fast reaction.

Yes", 3 in series and 2 in series, connected in parallel.

It is a 12 volt system. 2 batteries parralel.

See the pictures with my fist post.
 
Thanks for your fast reaction.

Yes", 3 in series and 2 in series, connected in parallel.

It is a 12 volt system. 2 batteries parralel.

See the pictures with my fist post.
in your first post the batteries connected serial!
Re solar panels - connecting parallel 3 series + 2 series is not the best thing to do.
 
The panels need to be connected (2 in series) in parallel with (2 in series) or all panels in parallel subject to being within the solar controller input current limit.

If you are using the solar charge controller to indicate the battery state it will give very poor inaccurate results, Ideally you need a battery monitor like the Victron BMV 712.

At the least, a voltmeter would be some help to indicate the battery state.

You need to find a specialist who knows what he/she is doing. A better clear diagram of your system showing all chargers would help.
state of charge.jpg


Mike
 
Last edited:
Goodmorging, Why it not right how i connect? How do you advive to connect the five solar panels? (My build is finished so no more wiring to the battery please :)) In the attachment a scedule how i connect it.
 

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The panels need to be connected (2 in series) in parallel with (2 in series) or all panels in parallel subject to being within the solar controller input current limit.

If you are using the solar charge controller to indicate the battery state it will give very poor inaccurate results, Ideally you need a battery monitor like the Victron BMV 712.

At the least, a voltmeter would be some help to indicate the battery state.

You need to find a specialist who knows what he/she is doing. A better clear diagram of your system showing all chargers would help.
View attachment 51114


Mike
The panels need to be connected (2 in series) in parallel with (2 in series) or all panels in parallel subject to being within the solar controller input current limit.

If you are using the solar charge controller to indicate the battery state it will give very poor inaccurate results, Ideally you need a battery monitor like the Victron BMV 712.

At the least, a voltmeter would be some help to indicate the battery state.

You need to find a specialist who knows what he/she is doing. A better clear diagram of your system showing all chargers would help.
View attachment 51114


Mike
Thanks Mike, so the only solution to have 5 panels is to connect them parallel?
 
so the only solution to have 5 panels is to connect them parallel?
That would be one solution, provided the input current limit, 50A, of the controller is not exceeded. I would recommend testing each panel independently before reconnecting in a suitable manner.

Mike
 
Odd numbers of panels can be difficult to work with. You either have them all in series or all in parallel. Otherwise you end up with some very off-the-wall configurations. Even numbers of panels are easier to work with. 2s2p is what I would use to establish a baseline for getting the system to work, assuming that it fits within the specifications of your solar charge controller.
 
That would be one solution, provided the input current limit, 50A, of the controller is not exceeded. I would recommend testing each panel independently before reconnecting in a suitable manner.

Mike
The panels produce 5,38A eage, so in parralel that is less than 30. My mmpt is 40a so that s no problem. Only my wires are 6mm2 and i think that is too small. What do you think? So there are 2 possibilities left. All in serie (I have a maxxfan and bagabox so that s not ideal beacause of shadow). 2 on 2 paralel (thats also not ideal. Buy an other on is not possible because they are sold out. What is the best of the not ideal situation? (Paralel 2 on 2 or all in series)
 
Jules, i have the Renogy 12V-12V 20Amp charger and it seems to be working great for me. I admit their help line was lame and I had to figure out how to make it work in my application. I have a truck and trailer. I wired the Renogy so that it will charge the trailer batteries either from the shore converter or from the truck power lead. Any questions I can answer?
 
Jules, i have the Renogy 12V-12V 20Amp charger and it seems to be working great for me. I admit their help line was lame and I had to figure out how to make it work in my application. I have a truck and trailer. I wired the Renogy so that it will charge the trailer batteries either from the shore converter or from the truck power lead. Any questions I can answer?
Hello, See my post: The panels produce 5,38A eage, so in parralel that is less than 30. My mmpt is 40a so that s no problem. Only my wires are 6mm2 and i think that is too small. What do you think? So there are 2 possibilities left. All in serie (I have a maxxfan and bagabox so that s not ideal beacause of shadow). 2 on 2 paralel (thats also not ideal. Buy an other on is not possible because they are sold out. What is the best of the not ideal situation? (Paralel 2 on 2 or all in series)
 
What is the best of the not ideal situation? (Paralel 2 on 2 or all in series)
All 5 in series is not possible because the controller is limited to 100V. The panels will have an OC voltage of around 22 volts, the limit would be 4 in series.
In parallel the maximum current is theory is 27 amps. In practice with panels flat on a camper roof you will have much less, just over 20 amps. 6mm2 cable is good for 50 amps. Combine the feeds to parallel as close as practical to the controller to reduce losses. At 20 amps one meter run of 6mm2 drops 0.13 volts.

Buy an other on is not possible because they are sold out
Any 100 watt panel would be ok , it does not need to be an exact match, just the same number of cells.

Mike
 
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