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eric-heiberg avatar image
eric-heiberg asked

CCGX shows float when in absorption -Easysolar 3kva 150/70

Hallo !

I changed the charging settings with a bluetooth dongle yesterday since my batteries (10 kw of recycled eletric car batteries - lithium ion) never charged more than 28,2 volts although the product sheet sheet says fully charged in at 28,7 (and 28 volts is 80% full).

Everything worked fine, but I never got to charge my batteries more than 28,2. The maximum charging was approx 28,3 -28,35, which i assume was the absorption voltage. Normally the absorption period was 9 minutes (longer somtimes due to deeper discharge....I think).


With the bluetooth dongle I changed the MPPT absorption to 28,7 volts and the float to 28,5 volts. I also put the absorption time to maximum 1 hour.

The voltage of 28,7 was reached at ca. 10:30 (se pic) with 27,6 Amps. The amps have decreased steadily since then, and now almost 3 hours later the Amps are at 8,9 (the voltage is still 28,7 volts).

However, the CCGX showed Float from 09:56. Shouldt it have showed absorption as the voltage is the same and the Amps are dropping (and not float)? The CCGX shows that the absorption period was from 09:46 -09:56.


It is the first time I have adjusted settings, so I would greatly appreciate some help here.


Thanks :-)


Eric


MPPT Controllersbattery chargingEasySolar All-in-One
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2 Answers
Guy Stewart (Victron Community Manager) avatar image
Guy Stewart (Victron Community Manager) answered ·

It looks like it is behaving as expected to me.

You have set the float voltage to be very close to the absorption voltage, which is fine for lithium.

The float voltage will act like an absorption state if the batteries can still absorb current. The MPPT will maintain the float voltage. As you have it so close, there is still charging to be done to maintain that high float voltage.

Generally you would expect the current to fall off more quickly than that, but that is neither here nor there.

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eric-heiberg avatar image
eric-heiberg answered ·

Thank you very much for your quick reply.

I hope it is okey that I ask you some moe questions:


I am guessing the the long absorption ("float") period was because I had a discharge down to 26,8 volts yesterday (sunday 14th of april).

QUESTION:
I am guessing the the long absorption ("float") period was because I had a discharge down to 26,8 volts yesterday (sunday 14th of april).

The current decreased to around 1 amp before sundown -does that mean that the absorption period is over?

Under you can see that the CCGX registrered a 10 minute float just before 10 O´clock.




Curious to see what happens tomorrow -from the history I can read that the float during the day (when I have not been there) is around 1,3 amps on the solar charger at daytime.

(while I had a fridge on which I have turened off now so there should not be any load)


Does this look right?:


QUESTION:
On april 14th I changed the settings on the mppt with a bluetooth dongle, and had got a 119 Error message. After reading the manual I restored the mppt to factory settings before putting in new values (I made sure the equalization was disabled).

I spoke with the dealer I bought the system from and he said that I have to make sure that the temperature compensation was shut off to avoid higher voltages -and that this might be on because I restored factory settings before I entered charging values. In april in Norway it can be below zero at night and +10 to +15 degrees celcius during the day. (Especially lately it has been cold at night, and clear skies all day).

I am not quite sure if I turned off the temperature compensation. Could this damage the battery in any way?
The solar system is on an island, and I will not be able to get there before a week or two....-is there any way to adjust settings on the MPPT (not Smart with built in bluetooth) remotely or do I need to be on-site with bluetooth?
I would like to buy the Smart Battery Sense (if needed), but I would then need a dongle for bluetooth in the VE:Direct port (which is now connected to the CCGX in my Easysolar). Solutions here?


Comment to Victron:
I also want to inform Victron that I have to hold the VE:Direct cable in the socket on the MPPT very still with my fingers and that I takes me many attempts to keep the blue light remaining on while adjusting settings with my other hand on my mobile phone. Is this a common problem ? Any way of solving this?
(The VE.Direct cable from the CCGX is also very loose, but stays in .....so far. I can not hear/see any click in function -How does it remain in?).


Thanks :-)


Eric


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