power going to grid and battery at the same time

[gumpster1981]

i have noticed the last couple of day when the sun has finally decided to show itself that as an example i could be producing 2KW from my array, the house is drawing 300w, and at the same time the battery will be charging at 650W with the remaining 1KW give or take being taken by the grid, this has me puzzled as i'm set on self consumption first mode so in my mind the battery should charge before any power goes to the grid in this instance, any thoughts?

thanks

[Rowenajess]

I have had the same problem in that the battery wouldn’t charge above 90% but today it won’t charge above 93% and diverting all the energy to the grid

[gumpster1981]

Think I’ve got to the bottom of it, seems it linked to the siting of the batteries in my loft and the cold weather we’re getting at the minute, the BMS throttles the charging current to protect the batteries, obviously not ideal as we want all the solar to go into the batteries before It goest to the grid, I’m going to try making an insulated cover to go over them and see how that performs, failing that the drastic solution will be to relocate them into a warmer area in the house, not my preferred solution or my wife’s as it would mean sacrificing a cupboard in the bedroom to accommodate

[Cr125mxer]

I’m glad someone thought of the issue with the temperature of the batteries.
I’ve had my solar running maybe 3 weeks, I collected and excitedly installed my batteries on Friday(only to find that 1 of the 4 delivered was a V2 and wouldn’t work with my BMS but that’s another story)

Since then I’ve been scratching my head trying to get all the settings right, I was very confused by only having 540w max charging the batteries and nearly over 1Kw going to the grid.

My batteries and inverter are installed in my garage so the temperature is very low at the moment.

I wasn’t overly impressed with the stacking brackets that are supplied and had thoughts of installing them in a modified data cabinet with a custom rear support (I have done this with large CCTV NVR’s in the past) I could then install a bit of basic climate control for the height of summer and depths of winter. Maybe just removing the sides the rest of the year.

With your setup in the loft have you had any issues with over heating to the hot weather?

[gumpster1981]

not had any overheating issues so far and we went through some pretty hot weather which had me worried, also didn't notice any drop in performance either due to heat, I'm sure the BMS will look after them in extreme conditions anyway, it is a bit annoying when I asked the installers before install if the batteries were effected by heat/cold conditions that would arise from fitting in the loft as I had a cupboard that would have housed it all nicely, obviously not to my wife's liking though.
so to cut a long story short, no I haven't had any adverse effects from the heat but yes I will be making an insulated enclosure to go over them for the winter, I'll then monitor the charge rates and if its still needs improvement step 2 will be to fit a small heater to the enclosure, maybe something like a heat pad used on seed trays, something very low wattage.