Is the AGM spiral preset algorithm suitable to be used with a REMCO flat plate100 ah AGM battery.

You need to find the manufacturers recommended settings and compare those with the preset, charge values for each preset in the manual. If you can not find manufacturers info, for a standard AGM I would recommend 14.4V absorption and 13.6V float or the closest you can get.

Thank you for the advice the datasheet for my remco 100ah agm battery. Shows the figures in the attached photo. I am unable to find what the tail current percentage should be set at. My research shows can be as low as 1% currently set at 4%. Any Adivce? My next issue is making sure the SOC as reported is correct as it shows 100% SOC with battery voltage at 11.4v which seems odd to me. Appreciate your help thank you. Kind regards Wayne Whitmore (attachments) [Screenshot_20241006-093752_Drive.jpg]

I would start with a tail current of 2% and see how the charge proceeds. If the current flat lines before 2% increase the tail current, if it is still falling then you can go lower. I use 1% on my Victron AGMs. When starting a battery monitor it goes to 100%. You need to give the battery a full charge so the monitor synchronises to a full battery and from then on it should be accurate.

I took your latest advice with the following results. The SOC was synchronized this morning 8.00am when bat voltage was reading 14.2. This afternoon at 5.00pm the voltage has dropped to 13.05 and by 6.00pm the voltage had dropped to 12.76v but the SOC is still showing 100% Charged. [Screenshot_20241006-113226] [Screenshot_20241006-113301] [Screenshot_20241007-180158] The charged voltage setting is 14.2v and float set at 13.5v. I have attached screen shots in two separate posts of my settings and the charge trends. Should I have expected the charge phase go to bulk or absorption after the voltage fell below the float setting of 13.5v? This is where by the end of the day my voltage seems to have very little capacity after charging all day with no draw on the system. The system is part of my 2023 Avida Esperance Motor home and when using just the leveling legs and putting out the slide out when parking for the night we do not have any capacity to use the microwave or jug with the inverter. I am questioning if my system is operating to achieve its best performance or maybe I have a battery issue? The batteries are 1 year old. Quick 100amp load test of the batteries showed they dropped to 11.5v but recovered soon after to 13V.

2nd set of screenshots. [Screenshot_20241006-111446] [Screenshot_20241007-173034] [Screenshot_20241007-173115] [Screenshot_20241006-113159]

Your charging from Solar is working well. The settings in your battery monitor (BMV) are good. The problem you have is that your BMV shunt is not detecting and discharge current. You may have a wiring error. See my FAQ for the common wiring issues and correct wiring. [image] Shunt / battery monitor not reading the correct SOC/ Amps, missing solar, decreasing daily or other misreading problems DIY This topic covers the SOC / Amps reported by BMV battery monitors, SmartShunts, Lynx BMSs and Lynx Shunts and will just be called shunt below. It is also assumed that the shunt is monitoring the domestic / house / cabin battery bank and not engine start / bow thruster / winch / caravan mover battery banks. The problems may be one or more of the following The SOC decreases daily despite the solar charger or other charger(s) working. The SOC increasing when discharging and falling when charging…

Thank you for the detailed information. I will have to refer the issue back to the Motorhome dealer for rectification. Can I again ask my question about changing from float to absorption phase please. Should I expect the charge phase go to bulk or absorption after the voltage falls below the float setting of 13.5v?

Yes you should, but sometimes on aggregate displays of total solar is does not show. It should show on individual solar displays.

When checking my readings this morning I have an odd situation where one array has gone into float but the other has stayed in absorption even though both arrays are set up with exactly the same settings. What would be the explanation for this situation please? [Screenshot_20241006-113226] [Screenshot_20241006-113301] [Screenshot_20241008-072932]

If the 2 controllers are working independently then there will be minor voltage differences between the two units. As the batteries get full and very little current is required one will reach float conditions 1st and the other will provide all the required current. This is not usually an issue as the batteries ate being charged as fast as they will accept current. There is a way to network the SmartShunt and SmartSolar controllers using Bluetooth and I believe it is possible to get the controllers to work as a pair. Have a read of the manuals and the attached link VE Smart Networking

AGM charging algorithm

DIY

pwfarnell 7 October 2024 08:54 7

Your charging from Solar is working well. The settings in your battery monitor (BMV) are good. The problem you have is that your BMV shunt is not detecting and discharge current. You may have a wiring error. See my FAQ for the common wiring issues and correct wiring.

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AGM charging algorithm

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