Renogy Rover 40A settings for Ampere Time 200Ah Li

[mathtek]

I recently upgraded my 200Ah AGM deep cycle batteries to Ampere Time 200Ah, following Will's recommendation on his forum, as my AGM batteries are now 4 years old and not likely to last much longer in my desert climate where temps often exceed 104 F.

When I selected Li from the menu in the Rover, charging started at a reasonable 250W for the current conditions.

But upon reading the Ampere Time manual it recommended using the USER settings instead. When I selected those values charging was reduced to about 10W.

I started modifying the Rover settings to see what might be causing the sudden drop in charging power and found that it was the Boost Charge Voltage setting of 13.8 volts that was causing the Rover to throttle the charging.

I changed the value to 14.6V and the Rover started charging again at 250W. I repeated this a few times just to be sure it wasnt a fluke.

Also, the Bluetooth App for the Renogy kept saying I was at 100% SOC at 13.2V, when Ampere Time lists that as 70%.

I changed the Rover setting of Boost Charge Return Volt from 13.8 to 14.2, and then I got a more reasonable reading of 73% SOC on the Bluetooth App.

These two changes seem to have my Ampere Time 200Ah Li battery now charging as expected and properly displaying the SOC.

I have no idea how the Rover's software utilizes these parameters to determine charging and SOC, but these values seem to have resolved my initial problems with charging and displaying SOC.

Attached is a screen shot from the Renogy Rover Bluetooth App.

 

[sunshine_eggo]

Voltage is an unreliable way to establish SoC unless the battery has been completely at rest with no loads or charging for about 30 minutes.

 

[Dynoman]

I recently upgraded my 200Ah AGM deep cycle batteries to Ampere Time 200Ah, following Will's recommendation on his forum, as my AGM batteries are now 4 years old and not likely to last much longer in my desert climate where temps often exceed 104 F.

When I selected Li from the menu in the Rover, charging started at a reasonable 250W for the current conditions.

But upon reading the Ampere Time manual it recommended using the USER settings instead. When I selected those values charging was reduced to about 10W.

I started modifying the Rover settings to see what might be causing the sudden drop in charging power and found that it was the Boost Charge Voltage setting of 13.8 volts that was causing the Rover to throttle the charging.

I changed the value to 14.6V and the Rover started charging again at 250W. I repeated this a few times just to be sure it wasnt a fluke.

Also, the Bluetooth App for the Renogy kept saying I was at 100% SOC at 13.2V, when Ampere Time lists that as 70%.

I changed the Rover setting of Boost Charge Return Volt from 13.8 to 14.2, and then I got a more reasonable reading of 73% SOC on the Bluetooth App.

These two changes seem to have my Ampere Time 200Ah Li battery now charging as expected and properly displaying the SOC.

I have no idea how the Rover's software utilizes these parameters to determine charging and SOC, but these values seem to have resolved my initial problems with charging and displaying SOC.

Attached is a screen shot from the Renogy Rover Bluetooth App.

Yes you should use the USR settings. The Rover LI settings are to aggressive for Lifepo4 Batteries.
Set to USR & set:
High Voltage Disconnect 14.5v
Charge Limit Voltage14.1v
Equalization Charge Voltage 14.0v
Boost Charge Voltage 14.0v
Float Charge Volt 13.6v
Boost Char Return Volt 13.3v
Over Disc Return Volt 11.0v
Low voltage Alarm 10.9v
Over Discharge Volt 10.5v
Discharge Limit Volt 10v
Over Disc Delay Time 5s
Equalization Charge Time 0 Min
Boost Time 10 Min
Equalize Charge Interval 185 (Note this value cannot be 0 because controller can get stuck in boost mode)
Temp Comp 0A

Unplug temp sensor from the Renogy-40 amp Solar Charge Controller. Leaving it plugged in can skew charging. It is used for Lead Acid batteries and not Lifepo4.

These settings should get you started. You can adjust from there. These are the settings I use with Renogy Rover 40 amp SCC currently going on 3rd year.

Note that I find the Renogy Rover 40 amp SCC voltage display can be off by 0.1 or 0.2 volts (usually low) and this is common with this solar charge controller. So if Boost is set to 14.0 it will probably go to 14.1 or 14.2 volts (read with a good volt meter) which is a very high state of charge for Lifepo4. You can try higher, but at 14.1 or 14.2 volts Lifepo4 batteries are typically at least 95% charged or more.

The Renogy Rover 40 amp SCC is not a precision SCC, but can be used very effectively.

Your BMS in your battery will (or should) shut down your battery before any damage to the cells with overvoltage or undervoltage protection, but you don't want to use this feature to run your solar system since it is a failsafe. You need to program the Rover-40 Boost Voltage to a voltage below your BMS overvoltage and you need to remove your loads before the battery BMS goes into undervoltage or make sure the battery voltage never gets that low (this can be done with an automatic transfer switch when using inverter/grid power combination).

The SOC displayed by the Renogy Rover 40 amp SCC is determined by voltage and as previously stated voltage is not accurate and can be off by a considerable amount. To get an accurate SOC a shunt is needed. The Victron Energy SmartShunt is one of the best currently on the market. It has Bluetooth that is displayed with an app on phone.

https://www.amazon.com/Victron-SmartShunt-500AMP-Bluetooth-Battery/dp/B0856PHNLX

I use the Victron BMV 712 that comes with a display and a few more features, but it cost more.

https://www.amazon.com/Victron-BMV-712-Battery-Monitor-Black/dp/B084M2XYK4

Hope this helps...

 

[mathtek]

Thank you all for your detailed and helpful advice.

Yes, I followed the advice given in the Ampere Time manual to completely disconnect the battery and let it rest for 15 minutes before measuring voltage, and then use their lookup table. I got similar results from the Renogy Bluetooth App when the controller was disconnected from the solar panels, and the load function was disabled, Perhaps its just a fluke, but the voltage values of the Rover under those conditions were exactly what I measured myself and the SOC displayed was close to what Ampere Time gave for the same voltages.

I dont know what make/model of LiFePO4 battery you are using, but the Ampere Time manual specifically states that charging is to be done from 14.2V to 14.6V, and the high end cutoff is 15V. This must be what is required to work with their cells and BMS, so the values I used were high compared to yours.

 

[Dynoman]

Thank you all for your detailed and helpful advice.

Yes, I followed the advice given in the Ampere Time manual to completely disconnect the battery and let it rest for 15 minutes before measuring voltage, and then use their lookup table. I got similar results from the Renogy Bluetooth App when the controller was disconnected from the solar panels, and the load function was disabled, Perhaps its just a fluke, but the voltage values of the Rover under those conditions were exactly what I measured myself and the SOC displayed was close to what Ampere Time gave for the same voltages.

I dont know what make/model of LiFePO4 battery you are using, but the Ampere Time manual specifically states that charging is to be done from 14.2V to 14.6V, and the high end cutoff is 15V. This must be what is required to work with their cells and BMS, so the values I used were high compared to yours.

Well, I may be a little conservative with the boost setting, but everything I have read says:

Min voltage for LiFePO4 Cells is usually 2.5v or 4 cells x 2.5 = 10 Volts
Max voltage for LiFePO4 Cells is usually 3.65v or 4 cells x 3.65 = 14.6 Volts

So yes, the battery can be charged to 14.6 Volts, but you are taking it to its absolute maximum without room for error. And add to that the Rover will probably go over that by 0.1 to 0.2 volts and could be charging to 14.7 or 14.8 volts. Try setting a boost value to no higher than 14.2 volts to start.

For Example. I have a Rover 40 and a Rover 100 charging two 271 ah 24 volt battery banks in parallel. The boost is set to 14 volts (28 volts in a 24 volt system). The Rovers both routinely charge to 28.17 volts measured by an accurate volt meter even though the Rovers display 28 volts. This is 0.17 volts over setting. My observations are charging the batteries to 28.17 Volts and holding it there for 10 to 20 minutes charges them to a minimum of 95%. The Rovers then fall back to a float voltage of 27.35 volts while suppling loads when there is enough sunlight.

Try setting the Boost to 14.2 volts realizing is will probably go to approximately 14.4 volts measured by an accurate volt meter. You can always set it higher if needed. Best to start low and work higher in my opinion.

A high end cut off of 15 volts probably risk damage to the cells in the battery, depending how long held at that voltage, although if the Rover works as expected with a boost setting of 14.2 volts it should keep the max voltage at 14.4 volts. Also the BMS should kick in to save the battery.

Try clicking Resources at the top of the page of this Forum. There is a host of information in that section of the forum. Look for Lifepo4 charge curve plots. Note how little is obtained by going above 14.2 volts.

The battery SOC displayed on the Rover is inaccurate. Every once in a while it will match up to a correct value, but that is not the norm. To get an accurate SOC a shunt is usually recommended. Here is another listing that cost less. Not as good as the Victron, but works fairly well with good reviews.

Robot Check

According to their listing on Amazon the battery can be charged at 14.2 to 14.6. A boost setting of 14.2 volts on the Rover would be approximately 14.4 charging volts and in the middle of the range 14.2v to 14.6v. Good luck with your battery. In time you will find the sweet spot Rover settings for your battery.

 

[mathtek]

I recently upgraded my 200Ah AGM deep cycle batteries to Ampere Time 200Ah, following Will's recommendation on his forum, as my AGM batteries are now 4 years old and not likely to last much longer in my desert climate where temps often exceed 104 F.

When I selected Li from the menu in the Rover, charging started at a reasonable 250W for the current conditions.

But upon reading the Ampere Time manual it recommended using the USER settings instead. When I selected those values charging was reduced to about 10W.

I started modifying the Rover settings to see what might be causing the sudden drop in charging power and found that it was the Boost Charge Voltage setting of 13.8 volts that was causing the Rover to throttle the charging.

I changed the value to 14.6V and the Rover started charging again at 250W. I repeated this a few times just to be sure it wasnt a fluke.

Also, the Bluetooth App for the Renogy kept saying I was at 100% SOC at 13.2V, when Ampere Time lists that as 70%.

I changed the Rover setting of Boost Charge Return Volt from 13.8 to 14.2, and then I got a more reasonable reading of 73% SOC on the Bluetooth App.

These two changes seem to have my Ampere Time 200Ah Li battery now charging as expected and properly displaying the SOC.

I have no idea how the Rover's software utilizes these parameters to determine charging and SOC, but these values seem to have resolved my initial problems with charging and displaying SOC.

Attached is a screen shot from the Renogy Rover Bluetooth App.

I am reading the Ampere Time manual, and the values they give are most likely due to the presence of the BMS, as I do not access the cells directly.

You could be on to something about the high values being an issue for the Renogy Rover. I just dont know enough about the Rover's algorithms to be certain of that.

I have not had any issue with the Ampere Time battery, and its overcharge protection circuit provides some peace of mind.

 

[mikefitz]

Ideally the charger should control the charging process not the BMS. Amper time may not have completely balanced cells so high cell protection may stop the charge process

 

[mathtek]

Overvoltage protection is a part of controlling the charging process. What is ideal about only the charger providing overvoltage protection, and not the BMS too?

I'd like to add that I would have simply used the Renogy Rover 40A defaults, which are designed according to the Renogy manual for nominal 12.8V LFP batteries, which is the case for the Ampere Time, but not other types of Li batteries; but, I noticed that Renogy defaults the Over-voltage Warning to 16V, but Ampere Time specifies in their manual that high voltage cutoff is 15V. That's an entire volt below what Renogy considers a warning! So, I was compelled to go to the USER battery specs, and thats when I had some issues with charging, which seem to be resolved for now.

 

[mikefitz]

Over volt protection if continually applied by the BMS may,
Stress the control fets in BMS
Prevent cell balance
Cause voltage surges in the system
Keeps the high cell in maximum state of charge, perhaps accelerating ageing

 

[mathtek]

That sounds like second-guessing the competence of the manufacturer. I dont know what BMS Ampere Time is using in their 12V LFP 200Ah Plus battery, but they are based in Hong Kong, where some of the brainiest electronics engineers in the world are located.

 

[Alexank]

Equalize Charge Interval 185 (Note this value cannot be 0 because controller can get stuck in boost mode)
Temp Comp 0A

Where did that above info come from?

It's interesting because when using the Rover 40 default LI profile that is exactly what seems to be happening, it stays on boost permanently which I find very annoying!

 

[Dynoman]

Where did that above info come from?

It's interesting because when using the Rover 40 default LI profile that is exactly what seems to be happening, it stays on boost permanently which I find very annoying!

Equalize Charge Interval 185 (Note this value cannot be 0 because controller can get stuck in boost mode) I found this out by trial and error.

Made the value 0 and stayed in boost. made the value 185 and went from boost to float after programmed boost time. If you are having problems with a Rover using Lifepo4 cells then try programming it with the above values in Post #3 and see if it helps. Works very well with my Rover 40.

 

[Risky Rob]

Yes you should use the USR settings. The Rover LI settings are to aggressive for Lifepo4 Batteries.
Set to USR & set:
High Voltage Disconnect 14.5v
Charge Limit Voltage14.1v
Equalization Charge Voltage 14.0v
Boost Charge Voltage 14.0v
Float Charge Volt 13.6v
Boost Char Return Volt 13.3v
Over Disc Return Volt 11.0v
Low voltage Alarm 10.9v
Over Discharge Volt 10.5v
Discharge Limit Volt 10v
Over Disc Delay Time 5s
Equalization Charge Time 0 Min
Boost Time 10 Min
Equalize Charge Interval 185 (Note this value cannot be 0 because controller can get stuck in boost mode)
Temp Comp 0A

Unplug temp sensor from the Renogy-40 amp Solar Charge Controller. Leaving it plugged in can skew charging. It is used for Lead Acid batteries and not Lifepo4.

These settings should get you started. You can adjust from there. These are the settings I use with Renogy Rover 40 amp SCC currently going on 3rd year.

Note that I find the Renogy Rover 40 amp SCC voltage display can be off by 0.1 or 0.2 volts (usually low) and this is common with this solar charge controller. So if Boost is set to 14.0 it will probably go to 14.1 or 14.2 volts (read with a good volt meter) which is a very high state of charge for Lifepo4. You can try higher, but at 14.1 or 14.2 volts Lifepo4 batteries are typically at least 95% charged or more.

The Renogy Rover 40 amp SCC is not a precision SCC, but can be used very effectively.

Your BMS in your battery will (or should) shut down your battery before any damage to the cells with overvoltage or undervoltage protection, but you don't want to use this feature to run your solar system since it is a failsafe. You need to program the Rover-40 Boost Voltage to a voltage below your BMS overvoltage and you need to remove your loads before the battery BMS goes into undervoltage or make sure the battery voltage never gets that low (this can be done with an automatic transfer switch when using inverter/grid power combination).

The SOC displayed by the Renogy Rover 40 amp SCC is determined by voltage and as previously stated voltage is not accurate and can be off by a considerable amount. To get an accurate SOC a shunt is needed. The Victron Energy SmartShunt is one of the best currently on the market. It has Bluetooth that is displayed with an app on phone.

https://www.amazon.com/Victron-SmartShunt-500AMP-Bluetooth-Battery/dp/B0856PHNLX

I use the Victron BMV 712 that comes with a display and a few more features, but it cost more.

https://www.amazon.com/Victron-BMV-712-Battery-Monitor-Black/dp/B084M2XYK4

Hope this helps...

Thanks for this. I set up the Renogy BT app and programmed these setting for my LiFePO4 bank.

 

[Dynoman]

Thanks for this. I set up the Renogy BT app and programmed these setting for my LiFePO4 bank.

Your most welcome. The settings work good for my Renogy Rover LI 40 and 100 amp using Lifepo4 cells going on my 3rd year now. The settings may need to be tweaked for your system, but should be a good starting point.

 

[lightmail]

Equalize Charge Interval 185 (Note this value cannot be 0 because controller can get stuck in boost mode) I found this out by trial and error.

Made the value 0 and stayed in boost. made the value 185 and went from boost to float after programmed boost time. If you are having problems with a Rover using Lifepo4 cells then try programming it with the above values in Post #3 and see if it helps. Works very well with my Rover 40.

In a previous post you put 0 instead of 185 because it is a lithium battery, Is 185 the right value. Thanks...

 

[Dynoman]

In a previous post you put 0 instead of 185 because it is a lithium battery, Is 185 the right value. Thanks...

As far as I know all of my post list Equalize Charge Interval(Days) 185 (Must not be zero or Rover will stay in boost mode).
If not please let me know where the post is so I can correct it.

 

[lightmail]

As far as I know all of my post list Equalize Charge Interval(Days) 185 (Must not be zero or Rover will stay in boost mode).
If not please let me know where the post is so I can correct it.

Sat. 10:28 Sept 10 2022
Equalize Charge Interval(Days) 185 (Must not be zero or Rover will stay in boost mode)
Number of days between equalizing lead acid batteries. Not used for Lifepo4 (July 9th above in this thread you posted what seems contradictory) ( Equalize Charge Interval 185 (Note this value cannot be 0 because controller can get stuck in boost mode) Am I missing something? Please let me know. Thanks....

 

[Risky Rob]

Sat. 10:28 Sept 10 2022
Equalize Charge Interval(Days) 185 (Must not be zero or Rover will stay in boost mode)
Number of days between equalizing lead acid batteries. Not used for Lifepo4 (July 9th above in this thread you posted what seems contradictory) ( Equalize Charge Interval 185 (Note this value cannot be 0 because controller can get stuck in boost mode) Am I missing something? Please let me know. Thanks....

Isn't setting the ECI to 185 for lithium batteries equivalent to eliminating it?

 

[Dynoman]

Sat. 10:28 Sept 10 2022
Equalize Charge Interval(Days) 185 (Must not be zero or Rover will stay in boost mode)
Number of days between equalizing lead acid batteries. Not used for Lifepo4 (July 9th above in this thread you posted what seems contradictory) ( Equalize Charge Interval 185 (Note this value cannot be 0 because controller can get stuck in boost mode) Am I missing something? Please let me know. Thanks....

@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...

 

[lightmail]

@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

Isn't setting the ECI to 185 for lithium batteries equivalent to eliminating it?

That seems to be correct as Dynoman explains.