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Renogy Rover 40A settings for Ampere Time 200Ah Li

@Risky Rob

The Equalize is a function for flooded lead acid batteries. Occasionally flooded lead acid batteries (ones with caps to fill water) should be charged to a higher than normal value to clean the plates so to speak.

Lifepo4 batteries do not need Equalize, but in the USER setting for the Rover Solar Charge Controller the Equalize Charge Interval(Days) should be set to 185 and not 0 because the Rover will get stuck in boost and never transition to float.

When the Equalize is called in every 185 days it still will not happen because the time is set for 0 minutes. Equalize Charge Time(Min) 0.

Hopefully this answers the question or confusion...
Thank you, I seem to have read it incorrectly. I have never seen the 185 thing before. No one takes the Rover's Equalize charge Interval seriously, I don't know why. Aside from this is the Equalize charge voltage even necessary. Can that value be just 0 instead of 14 volts as your July 9 shows, 3rd value down. Your way of explaining these things is so valuable. Now I understand how these values effect one another. Thanks again.
 
Thank you, I seem to have read it incorrectly. I have never seen the 185 thing before. No one takes the Rover's Equalize charge Interval seriously, I don't know why. Aside from this is the Equalize charge voltage even necessary. Can that value be just 0 instead of 14 volts as your July 9 shows, 3rd value down. Your way of explaining these things is so valuable. Now I understand how these values effect one another. Thanks again.

It is probably best to set equalize the same as boost voltage. Setting to 0 could cause problems in the Rovers software code.
 
Question:
I'm seeing some numbers suggested here for AmpereTime Batteries that I can't find in their manuals... Can someone please confirm the correct settings?
 

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Question:
I'm seeing some numbers suggested here for AmpereTime Batteries that I can't find in their manuals... Can someone please confirm the correct settings?

What solar charge controller is used in your system? Is it a Renogy Rover? If so check out the following message.


Also reading the entire thread this message is in would probably be helpful. It is mostly for a Chins battery, but would probably be helpful for the AmpereTime battery as well.
 
What solar charge controller is used in your system? Is it a Renogy Rover? If so check out the following message.


Also reading the entire thread this message is in would probably be helpful. It is mostly for a Chins battery, but would probably be helpful for the AmpereTime battery as well.
I bought a Renogy Rover 40 A... Haven't received it yet. Are you familiar w/ it? Do you know pls the drain current when not charging, at night? Second, Will it clear the settings by disconnecting the battery at night, or does the device has some kind of internal battery for the memory?
 
I bought a Renogy Rover 40 A... Haven't received it yet. Are you familiar w/ it? Do you know pls the drain current when not charging, at night? Second, Will it clear the settings by disconnecting the battery at night, or does the device has some kind of internal battery for the memory?

Yes I have a Renogy Rover 40 amp solar charge controller.

The Renogy Rover 40 amp self consumption is less than 1.4 Watt looking at the spec on page 27 of the manual (≤100mA @ 12V ≤58mA @ 24V)

It does not clear the programmed settings when battery power is removed.

I would see no benefit disconnecting the Rover 40 from the battery at night. I just leave it connected to the battery all the time.

I again suggest reading this message and thread you will probably find it helpful. Just click on the link to go there.


I have attached the Rover manual.
 

Attachments

  • Renogy Rover Li 20-30-40 Amp 12V-24V MPPT SSC Manual Ver 1_3.pdf
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Yes I have a Renogy Rover 40 amp solar charge controller.
The Renogy Rover 40 amp self consumption is less than 1.4 Watt looking at the spec on page 27 of the manual (≤100mA @ 12V ≤58mA @ 24V)
It does not clear the programmed settings when battery power is removed.
I would see no benefit disconnecting the Rover 40 from the battery at night. I just leave it connected to the battery all the time.
I again suggest reading this message and thread you will probably find it helpful. Just click on the link to go there.
I have attached the Rover manual.
The issue is that I'm planning to combine the Rover w/ an Amperetime 40A AC charger. Initially, I thought I can keep both connected in parallel but Customer Service from AmpereTime offered a weird explanation and suggested disconnecting the controller while charging with AC.

I read in the manual you provided the max voltage for the Rover is 100V. I was planning to connect four Renogy 100W panels in a series. The open- circuit-max-voltage of each panel is 24.3V, so the series can produce 97.2V maybe too close to the max of the Rover.
I also saw a review in youtube where someone describe 100V capacitors on the Rover input circuit.
 
The issue is that I'm planning to combine the Rover w/ an Amperetime 40A AC charger. Initially, I thought I can keep both connected in parallel but Customer Service from AmpereTime offered a weird explanation and suggested disconnecting the controller while charging with AC.

I read in the manual you provided the max voltage for the Rover is 100V. I was planning to connect four Renogy 100W panels in a series. The open- circuit-max-voltage of each panel is 24.3V, so the series can produce 97.2V maybe too close to the max of the Rover.
I also saw a review in youtube where someone describe 100V capacitors on the Rover input circuit.

Assuming a 12 volt Solar System:

Yes, the 4 x 100 watt panels in series at 24.3 VOC is too close for comfort for the Rover 40 amp solar charge controller 100 Volt solar max input. There is a chart that list temperature vs solar panel Voltage Open Circuit (VOC) output (will look for it). When the outside temp is cold the solar panel output rises and it would overvoltage the Rover 40 and possibly destroy it.

A good option would be to place 2 solar panels in series and then place the 2 series panels x 2 in parallel. This would give a series parallel wiring configuration for the panels. From the 4 x 100 watt panels this would output 48.6 VOC and no overvoltage problems. The Voltage with be cut in half and current output will double, but that should not be a problem. The panels can still be mounted 4 in a row if needed, but wired series parallel.

Assuming a 12 volt system:
In perfect 100% output the panels produce P/E = I 400w/12 = 33.3 amps output from the panels and in reality, probably around 25 or so amps due to losses input to the battery.

It would be possible to charge the battery at 33.3a Solar + 40a charger = 73.3 amps charging which may be a problem depending on the specs of the battery. I assume one 12 volt Lifepo4 battery in the system. Many Lifepo4 batteries are rated at .5C or 50% charging of the AH rating which if this is a 100 AH battery 50 amps charging would be max. Be a good idea for you to look into the battery specs and see if this is the situation.

I would leave the Rover 40 connected all the time to the battery and only connect the battery charger when needed to charge during cloudy days / at night if needed, but I don't know your circumstances.

Looking at the attachments from FilterGuy on the DIY Solar Power forum should be useful. One is for cold over voltage and other for configuring solar panels like the series parallel config above. FilterGuy and others have very good helpful documents in the Resources tab at the top of the page. Click on it and look around and download.

The best thing to do is research the project fully before implementation.
 

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  • Adjusting Panel Voc for temperature.pdf
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  • Solar Array OCP .pdf
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Assuming a 12 volt Solar System:

Yes, the 4 x 100 watt panels in series at 24.3 VOC is too close for comfort for the Rover 40 amp solar charge controller 100 Volt solar max input. There is a chart that list temperature vs solar panel Voltage Open Circuit (VOC) output (will look for it). When the outside temp is cold the solar panel output rises and it would overvoltage the Rover 40 and possibly destroy it.

A good option would be to place 2 solar panels in series and then place the 2 series panels x 2 in parallel. This would give a series parallel wiring configuration for the panels. From the 4 x 100 watt panels this would output 48.6 VOC and no overvoltage problems. The Voltage with be cut in half and current output will double, but that should not be a problem. The panels can still be mounted 4 in a row if needed, but wired series parallel.

Assuming a 12 volt system:
In perfect 100% output the panels produce P/E = I 400w/12 = 33.3 amps output from the panels and in reality, probably around 25 or so amps due to losses input to the battery.

It would be possible to charge the battery at 33.3a Solar + 40a charger = 73.3 amps charging which may be a problem depending on the specs of the battery. I assume one 12 volt Lifepo4 battery in the system. Many Lifepo4 batteries are rated at .5C or 50% charging of the AH rating which if this is a 100 AH battery 50 amps charging would be max. Be a good idea for you to look into the battery specs and see if this is the situation.

I would leave the Rover 40 connected all the time to the battery and only connect the battery charger when needed to charge during cloudy days / at night if needed, but I don't know your circumstances.

Looking at the attachments from FilterGuy on the DIY Solar Power forum should be useful. One is for cold over voltage and other for configuring solar panels like the series parallel config above. FilterGuy and others have very good helpful documents in the Resources tab at the top of the page. Click on it and look around and download.

The best thing to do is research the project fully before implementation.


The battery is 200AH and can support 73A charging (Amperetime 200AH Plus, BMS 200A).
The problem is any possible interaction between the AC Charger and the Rover Li.

This system will be installed in a place where AC power is available randomly for only 6-7 hours a day. Occasionally less than that.

I would like to use the Panels and the Rover's 400W during the day -When no AC is available- to charge the battery or to avoid its discharge when a load of 400W or less is connected. This way I will preserve the battery power for the night.

When the AC is available, I would prefer to use the AC Charger. It is faster and safer. It can sustain 40A and fully charge the battery in 5 hours.

Worst case without AC:
During the night:
- up to three fans of around 60W from 10 to 7 PM = 180Wx9 Hours =1620W,
- Plus a couple of 20w lamps, 3-4 hours = 160W,
- Plus One TV an hour 45W...

This is around 1.8 KW. The battery can provide up to 12x200=2400W. It will be discharged during the night maybe to 25%.

During the day the load will be a small Freeze of around 100W (from 11 AM to 4 PM), an occasional lamp, a TV, a FAN, etc. Less than 200W total. Around 200-300W from the Rover will go to charge and the other 100-200 will go to the different loads connected.

These are draft numbers not considering the inverter efficiency etc, etc.

I'm curious why Renogy is recommending the same both configurations (Series and parallel) and the Rover's manually states it will disconnect automatically if the panel voltage goes over 100V.
 
The battery is 200AH and can support 73A charging (Amperetime 200AH Plus, BMS 200A).
The problem is any possible interaction between the AC Charger and the Rover Li.

This system will be installed in a place where AC power is available randomly for only 6-7 hours a day. Occasionally less than that.

I would like to use the Panels and the Rover's 400W during the day -When no AC is available- to charge the battery or to avoid its discharge when a load of 400W or less is connected. This way I will preserve the battery power for the night.

When the AC is available, I would prefer to use the AC Charger. It is faster and safer. It can sustain 40A and fully charge the battery in 5 hours.

Worst case without AC:
During the night:
- up to three fans of around 60W from 10 to 7 PM = 180Wx9 Hours =1620W,
- Plus a couple of 20w lamps, 3-4 hours = 160W,
- Plus One TV an hour 45W...

This is around 1.8 KW. The battery can provide up to 12x200=2400W. It will be discharged during the night maybe to 25%.

During the day the load will be a small Freeze of around 100W (from 11 AM to 4 PM), an occasional lamp, a TV, a FAN, etc. Less than 200W total. Around 200-300W from the Rover will go to charge and the other 100-200 will go to the different loads connected.

These are draft numbers not considering the inverter efficiency etc, etc.

I'm curious why Renogy is recommending the same both configurations (Series and parallel) and the Rover's manually states it will disconnect automatically if the panel voltage goes over 100V.

Looked up the Ampere Time 200AH Plus, BMS 200AH Specs and looks like a really good battery.

I have charged Lifepo4 batteries with a charger and the Rover 40 (at the same time) many times with no problems. Everything I have read has described charging Lifepo4 battery(s) from multiple sources OK as long as don't go over the charge capacity of the battery. The Ampere Time 200AH Plus, BMS 200AH battery can discharge/charge at 200 amps rating so all should be good.

I would suggest setting up the Rover 40 with the USER settings as listed in previous message and charge with both the Rover & the Ampere Time charger at the same time and see how it goes. There should be no problems.

You may have a problem with the battery charger with the AC power going on/off. Hopefully the Ampere time 40A AC charger is durable and can handle the power going on/off as you describe. Probably a good idea to keep a eye on the Ampere time 40A AC charger when the system is first turned on and for some time after until it proves its durability.

With wiring the solar panels series parallel the solar panel voltage will not go above about 50 volts so there is no concern of the 100 volt limit.

Wire two 100 watt panels in series. Do this twice so there are 2 sets of two 100 watt panels in series. Take the 2 sets of two 100 watt panels in series and wire them in parallel. The voltage will be cut in half and the current will double with no loss of power output from the panels.

With The open- circuit-max-voltage of each panel rated 24.3V and the 4 panel series can produce 97.2V:
I strongly recommend DO NOT wire the 4 panels in series as this will probably destroy the Rover 40 in time. The Rover 40 may handle going over 100 volts at first (May Not), but it will be damaged or destroyed. It is NEVER recommended to exceed the solar panel voltage input to a solar charge controller.

The plan you list looks Like very good place to start. As you say there are still some unknowns.

What inverter are you considering for your system?
 
Looked up the Ampere Time 200AH Plus, BMS 200AH Specs and looks like a really good battery.

I have charged Lifepo4 batteries with a charger and the Rover 40 (at the same time) many times with no problems. Everything I have read has described charging Lifepo4 battery(s) from multiple sources OK as long as don't go over the charge capacity of the battery. The Ampere Time 200AH Plus, BMS 200AH battery can discharge/charge at 200 amps rating so all should be good.
=> I know...

There are two potential problems:

1) Any transient that the controller may produce that can damage the AC charger or even the Inverter. This can happen even w/ the inverter and the AC charger off but still connected to the battery. Worst if the BMS disconnects the bat. I want to measure the voltage w/ the circuit below.

2) Overcharging by combining the AC charger w/ the solar controller. No because the total current is too high but because the Rover Li continues charging even though the battery is full.

1669330006859.png
I would suggest setting up the Rover 40 with the USER settings as listed in previous message and charge with both the Rover & the Ampere Time charger at the same time and see how it goes. There should be no problems.
=>Still researching this. A lot of different values and recommendations. I'm lost here.
The Renogy DC Home only allows setting a few values. The previous Renogy BT app does not work w/ my Samsung Galaxy.
I'm pending to test using other devices.
There is a Solar App that appears to work but closes by itself when saving the custom values.

=>I'm editing my post to add that I was able to install the Renogy BT app on an older phone.
But, I tested and I think the Rover forgot the settings after 12 hours disconnected. Need to repeat the test to make sure.

Take a look at this link: https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/


You may have a problem with the battery charger with the AC power going on/off. Hopefully the Ampere time 40A AC charger is durable and can handle the power going on/off as you describe. Probably a good idea to keep a eye on the Ampere time 40A AC charger when the system is first turned on and for some time after until it proves its durability.
=>Why?
I was even considering using the panels (maybe another two) instead of the AC to feed the AC charger. The charge can work from 100 to 220V

With wiring the solar panels series parallel the solar panel voltage will not go above about 50 volts so there is no concern of the 100 volt limit.
Wire two 100 watt panels in series. Do this twice so there are 2 sets of two 100 watt panels in series. Take the 2 sets of two 100 watt panels in series and wire them in parallel. The voltage will be cut in half and the current will double with no loss of power output from the panels.
With The open- circuit-max-voltage of each panel rated 24.3V and the 4 panel series can produce 97.2V:
I strongly recommend DO NOT wire the 4 panels in series as this will probably destroy the Rover 40 in time. The Rover 40 may handle going over 100 volts at first (May Not), but it will be damaged or destroyed. It is NEVER recommended to exceed the solar panel voltage input to a solar charge controller.

=>Yes, I Understand this.
I'm just wondering why Renogy is also recommending the series configuration. They even include a 10A fuse to be used with the series. I bought their 400W premium kit.

1669349993927.png

The plan you list looks Like very good place to start. As you say there are still some unknowns.
What inverter are you considering for your system?
=> Below is a link to the inverter. I have used similar devices in the past. They are cheap, efficient and very reliable. I will use the 1000W. My load will never go over 400-600W. It also works ok w/ 15V battery and no load consumption when off.


Another thing that I don't understand is why the Rover Li Load Control is only for 20A. Using 12V=>240W... Practically non-useful for anything. Probably because they don't want to expend in low voltage high current relay.
 
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=> I know...

There are two potential problems:

1) Any transient that the controller may produce that can damage the AC charger or even the Inverter. This can happen even w/ the inverter and the AC charger off but still connected to the battery. Worst if the BMS disconnects the bat. I want to measure the voltage w/ the circuit below.

2) Overcharging by combining the AC charger w/ the solar controller. No because the total current is too high but because the Rover Li continues charging even though the battery is full.

View attachment 121699

=>Still researching this. A lot of different values and recommendations. I'm lost here.
The Renogy DC Home only allows setting a few values. The previous Renogy BT app does not work w/ my Samsung Galaxy.
I'm pending to test using other devices.
There is a Solar App that appears to work but closes by itself when saving the custom values.

=>I'm editing my post to add that I was able to install the Renogy BT app on an older phone.
But, I tested and I think the Rover forgot the settings after 12 hours disconnected. Need to repeat the test to make sure.

Take a look at this link: https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/



=>Why?
I was even considering using the panels (maybe another two) instead of the AC to feed the AC charger. The charge can work from 100 to 220V



=>Yes, I Understand this.
I'm just wondering why Renogy is also recommending the series configuration. They even include a 10A fuse to be used with the series. I bought their 400W premium kit.

View attachment 121717


=> Below is a link to the inverter. I have used similar devices in the past. They are cheap, efficient and very reliable. I will use the 1000W. My load will never go over 400-600W. It also works ok w/ 15V battery and no load consumption when off.


Another thing that I don't understand is why the Rover Li Load Control is only for 20A. Using 12V=>240W... Practically non-useful for anything. Probably because they don't want to expend in low voltage high current relay.

There are two potential problems:

1) Any transient that the controller may produce that can damage the AC charger or even the Inverter. This can happen even w/ the inverter and the AC charger off but still connected to the battery. Worst if the BMS disconnects the bat. I want to measure the voltage w/ the circuit below.
The Rover 40 should not cause any problems with transient.
BMS will not disconnect with Rover 40 setup properly although need to charge battery fully first to 14.6 volts first with Ampere Time Charger if possible and every once in a while charge to 14.6 volts with same charger to keep Lifepo4 cells in battery top balanced.
I measure voltage with a voltmeter.

2) Overcharging by combining the AC charger w/ the solar controller. No because the total current is too high but because the Rover Li continues charging even though the battery is full.
Problem 2) can be eliminated by ensuring the Rover 40 is programmed correctly as described here.

I was even considering using the panels (maybe another two) instead of the AC to feed the AC charger. The charge can work from 100 to 220V
Solar Panels cannot be used to power the AC charger, because the panels only produce DC.

One possibility would be to use an Inverter/Charger that has an Automatic Transfer Switch. It would replace the Ampere Time charger & inverter and can be programmed to switch to battery when power is lost. See link and attached manual.

I'm just wondering why Renogy is also recommending the series configuration. They even include a 10A fuse to be used with the series. I bought their 400W premium kit.
Yes, but the parallel connection that is displayed is the only safe way to install. You will need to get a 30 amp ANL fuse for the wiring the panels Positive connection to the Rover 40.

=>I'm editing my post to add that I was able to install the Renogy BT app on an older phone.
But, I tested and I think the Rover forgot the settings after 12 hours disconnected. Need to repeat the test to make sure.
I am glad the app works. My Rover 40 has been disconnected for extended periods and did not loose the settings. It is possible to do a reset in the Renogy BT app software and loose all settings.

Another thing that I don't understand is why the Rover Li Load Control is only for 20A. Using 12V=>240W... Practically non-useful for anything. Probably because they don't want to expend in low voltage high current relay.
The Load output is only meant to be used for low current loads like 12/24 VDC volt lighting. I recommend not using the load output. Run everything off the 120 VAC inverter.

=> Below is a link to the inverter. I have used similar devices in the past. They are cheap, efficient and very reliable. I will use the 1000W. My load will never go over 400-600W. It also works ok w/ 15V battery and no load consumption when off.
Looks like this inverter should work. The Sigineer Inverter/Charger may be a better purchase for the long run.
 

Attachments

  • Sigineer 600W-1KW-1.5KW-Inverter-Charger-Owners-Manual.pdf
    1.7 MB · Views: 7
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I don't think a 30A fuse will help.
The internal resistance of the cells will limit the current to less than 5A for each panel even in case of a short circuit. So, Using the series-parallel you suggested the current will never go over 9A.
The cable perfectly supports this current. So, worst case if the Rover Li short circuit the input, it will be ok for the panels and the cables.

Regarding "Solar Panels cannot be used to power the AC charger, because the panels only produce DC."
This does not matter. The charger is a switching power supply. It first rectifies the AC to DC.
There are only two potential problems:
1. Can the diodes support the double rms current? 99.99% yes!
2. The voltage variation below 90V (It will work ok from 90 to 240V). This is the real issue. I can use a relay w/ voltage control but defeat the purpose of having the MPTT.


1669409673889.png
 
I don't think a 30A fuse will help.
The internal resistance of the cells will limit the current to less than 5A for each panel even in case of a short circuit. So, Using the series-parallel you suggested the current will never go over 9A.
The cable perfectly supports this current. So, worst case if the Rover Li short circuit the input, it will be ok for the panels and the cables.

Agreed the 30A fuse is to high a value.

Message edited to correct errors and clarify.

Reading the specs for the Renogy 100 watt solar panel Short-Circuit Current (Isc): 5.21amps. 2 series panels is 5.21A.. Placing the 2 series panels x 2 in parallel (parallel current adds) 5.21 + 5.21 = 10.42 amps output possible from the 4 x 100 watt panels in the series parallel configuration. So the way it looks a 15 amp ANL fuse is probably advisable. The included 10 amp inline fuse could be installed, but may blow in a max solar panel output although the risk is small especially if the fuse is slow blow. I agree that it will be difficult to get more than 9 amps out of the series parallel configuration.

The fuse is to protect the Rover 40 in the event of a short in the solar panels or wiring. By protecting the Rover it also could someday save connected devices like battery and inverter. The 10 amp inline fuse is included in the kit might as well use it.

A Series Parallel configuration Drawing is attached.
 

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  • Screenshot 2022-11-25 205704.png
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I don't see any value in adding a fuse between the panels and the Rover.
As you said, The internal resistance of the panels will limit the current to 10A. The cables support two-three times this and the Rover is able to handle more than that too (The parallel configuration generates around 20 A).
So...The fuse is only an additional cost for nothing, another point of failure, just additional resistance added to the circuit and power lost -probably nothing/negligible but it will be there-.

No way the current goes beyond the limit.
Let's say the Rover is broken by over-voltage... If it goes open, then not current. if it goes short circuit, then the max current will be the panels short circuit max current (the 10A mentioned above), and that is ok for the cables etc.
 
I don't see any value in adding a fuse between the panels and the Rover.
As you said, The internal resistance of the panels will limit the current to 10A. The cables support two-three times this and the Rover is able to handle more than that too (The parallel configuration generates around 20 A).
So...The fuse is only an additional cost for nothing, another point of failure, just additional resistance added to the circuit and power lost -probably nothing/negligible but it will be there-.

No way the current goes beyond the limit.
Let's say the Rover is broken by over-voltage... If it goes open, then not current. if it goes short circuit, then the max current will be the panels short circuit max current (the 10A mentioned above), and that is ok for the cables etc.

It is my understanding a fuse between the solar panels and the solar charge controller on the positive wire is always recommended.

Sounds like you are well on your way. Good luck with your system. I hope it works well...
 
It is my understanding a fuse between the solar panels and the solar charge controller on the positive wire is always recommended.

Sounds like you are well on your way. Good luck with your system. I hope it works well...
I truly appreciate your advice. I have learned a lot! Thank you.
 
Sorry if someone has asked this, but I’m having trouble with Renogy 40A with EG4 24v batteries. The charge controller thinks they’re at 100% but voltage hangs around 26.6 so indicators on batteries never show more than two or three of 4 lights. I’m assuming the charge controller thinks they’re fully charged. Here’s where I have the settings and the battery specs. I’m hoping someone can check my numbers for me. ?1BB8DCEA-04A1-4101-AAB3-F716A02B1891.png
 

Attachments

  • EG4 LifePower4 24V Spec Sheet-2.1.0.pdf
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The recomended charge volts for the EG4 is 27.9 to 28.3, this corresponds to perhaps 13.9 to 14.2 in the charger.
I suggest 13.9 or 14 volts for boost charge.
What may be happening is cell overvolts in the battery is causing BMS protection stopping charge current. Can you monitor charge current?
You could try lowering the charge volts and increasing the boost period to give more time for cell balancing to occur.
Test the actual voltage at the Regogy controller output, the calibration can sometimes be in error, ( actual voltage higher than display).
Test for volt drops in the cables and connections.

Mike
 
Sorry if someone has asked this, but I’m having trouble with Renogy 40A with EG4 24v batteries. The charge controller thinks they’re at 100% but voltage hangs around 26.6 so indicators on batteries never show more than two or three of 4 lights. I’m assuming the charge controller thinks they’re fully charged. Here’s where I have the settings and the battery specs. I’m hoping someone can check my numbers for me. ?View attachment 130396

I agree... Try a boost voltage of 14 or less to start and increase the boost time to an hour or more. See if that helps. As was suggested the BMS may be going into over voltage and disconnecting the battery from charging as the top balance may need some correcting.

Also the charge indicator on the Rover 40 goes by the voltage and is totally inaccurate. The 4 LEDS on the EG4 is a much better indicator of the battery charge than the Renogy Rover 40 display. If the EG4 can be connected to a PC to monitor the BMS that should prove helpful.

For accurate battery charge status a shunt is probably the best. The Victron smart shunt is one of the better battery monitors on the market.

Also this time of year (winter in my area) it is hard to charge a 24 volt 200Ah battery with a 40 amp MPPT solar charge controller. If the Rover 40 amp is constantly in MPPT Charge Mode and never makes it to Boost and then Float Charge Mode the Rover 40 amp does not have enough solar production to fully charge the EG4. I know my Lifepo4 batteries have not been fully charged for about a month and during that time is usually less than 50% state of charge. December & January are the worst for solar production in my area with the sun low in the sky and many cloudy days. Solar production starts to improve in February and in the spring the batteries are fully charged during the day frequently and in the Summer almost every day the batteries are fully charged.

Another suggestion would be to click the link below and read this message and then read the entire thread. There is significant information on the Renogy Rover MPPT solar charge controller.
Hope it helps...
 
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