Victron Bluesolar and Equalisation

bigbrovar

Hi guys. I changed my charge controller from the chinese epsolar to victron energy bluesolar mppt charge controller 150/45

So far so good, been impressed by the controller especially the tracking speed in cloudy weather. However today is the first time the controller will be performing equalization of my batteries (220ah @ 24v, FLA with tubular plate) with my old controller (and inline with all documentation I read about equalization) equalization process takes minimum of 2 hours.. infact the user can set the number of hours the cc can perform equalization of the batteries but the default is 2 hours.

With victron blue solar, it is impossible to set equalisation time, you can only set the equalisation voltage. Here is the part of the bluesolar manual that talks about equalisation.

Automatic equalization

Automatic equalization is default set to ‘OFF’. By using the

configuration tool mpptprefs this setting can be configured with a

number between 1 (every day) and 250 (once every 250 days).

When automatic equalization is active, the absorption charge

will be followed by a voltage limited constant current period (see

table in section 3.5). The current is limited to 8% of the bulk

current for all VRLA (Gel or AGM) batteries and some flooded

batteries, and to 25% of the bulk current for all tubular plate

batteries and the user defined battery type. The bulk current is

the rated charger current unless a lower maximum current

setting has been chosen.

In case of all VRLA batteries and some flooded batteries

(algorithm number 0, 1, 2 or 3) automatic equalization ends

when the voltage limit maxV has been reached, or after

t = (absorption time)/8, whichever comes first.

For all tubular plate batteries and the user defined battery type

automatic equalization ends after t = (absorption time)/2.

When automatic equalisation is not completely finished within

one day, it will not resume the next day, the next equalisation

session will take place as determined by the day interval. 

My controller is set to algorithm number 2 which is the default. My question is, is 30 min of equalization enough? My battery are rarely discharged below 65% SOC in fact my average day to day cycle is at 70-85% SOC. My fear is just that the victron cc would leave my battery under equalized because most of what I read says equalization charge should be held for 2 hours to be effective.

bigbrovar

Took SG readings with my hydrometer some minutes after the above stated equalization attached is the SG level I got from my hydrometer for pretty much all the battery cells.

mcgivor

bigbrovar said:

Took SG readings with my hydrometer some minutes after the above stated equalisation attached is the SG level I got from my hydrometer for pretty much all the battery cells.

No attachment 

bigbrovar

mcgivor said:

bigbrovar said:

Took SG readings with my hydrometer some minutes after the above stated equalisation attached is the SG level I got from my hydrometer for pretty much all the battery cells.

No attachment 

I noticed image I uploaded did not reflect. I had to re-upload to imgur

bigbrovar

below is my charge cycle data for the last 30 days.. pulled from the controller history logs 

mcgivor

Manufacturers recommendations aside, that appears to be good, what temperature were the batteries when you took the readings? Who is the manufacturer of the battery?

bigbrovar

extended logs showing max battery voltage, Time spent in bulk, Absorption and float (all in minutes)

bigbrovar

mcgivor said:

Manufacturers recommendations aside, that appears to be good, what temperature were the batteries when you took the readings? Who is the manufacturer of the battery?

unfortunately unlike my former cheap chinese epsolar controller, the new victron bluesolar does not have external battery temperature sensor (neither do I have a battery temperature sensor) The victron energy has an ambiance sensor but the readings are not displayed. However from hand touch the battery seem to be around 29-30c.. its not warm or hot to touch. The battery is made in india.. by a company called luminous. It is of the model called "tubular battery" which is very popular in india https://www.luminouseshop.com/products/luminous-iltt-26048-220ah-tabular-battery its going to 9 months now since having the battery.

Estragon

It sounds like the default setting #2 may be for a VRLA battery of some type, with a 4hr timed absorb cycle.

The battery page doesn't appear to have some specs needed. It would help if you could find out from the manufacturer:
- recommended absorb voltage range
- recommended equalize voltage range
- recommended specific gravity at full charge.

Setting the controller to the tubular plate type profile looks like it would extend the EQ time to 2hrs, but it would be a good idea to check the above recommended values vs the profile values. With warm batteries and no remote temp sensor there is a risk of using too high voltage.