Load drawing from grid when it shouldnt
Hi everyone, I’m new on here, my first post.
I hope someone with more experience can help with an issue I’m having with my Sunsynk system.
I have a Sunsynk 5.5kw inverter
6 x 5.12 Sunsynk batteries (30KW total)
6 kw PV array
I don’t export any power at all (zero export) CT coil fitted to prevent export.
Location UK
Apart from this, everything is working fine, all settings have been checked by the support team, and I’ve had a firmware update just a few days ago
My issue is that I have just installed an unvented hot water cylinder to my house, and I’m topping up the heating of this for one hour overnight when there is no other load being used, so it’s pretty much running on its own.
The total load for the element is just 3kw, and with the fridge, led night lights etc, the total draw is no more than 3.5kw at any one time.
I grid charge the batteries regularly on cheap rate to keep SOC high,
The PV helps with this when it can during the day, and I never charge at the same time as this load is on.
I want this load to be totally supplied by the near fully charged batteries (which have been previously charged with PV+ Cheap rate grid).
But whatever I do with the settings, it still draws 1kw from the grid almost immediately it’s switched on, even with SOC as high as 95%, see attached graph screenshots below over a few days.
Maybe the batteries can’t supply 3kw? As it seems they peak out at just over 2.5kw whatever I try
Battery charge / discharge amp setting is at 100A in the battery settings.
Using basic maths this load is only approx 14 amps, for just one hour, so I thought the 30kw battery pack would easily handle this, and it’s nowhere near the max output of the inverter (5.5kw) so I’m at a loss as to why it’s drawing from the grid at all. (I accept the 20-85W self consumption needs to be there, but this is a tiny amount compared with the 1kw+ its drawing)
Has anyone else had a similar issue,? Am I expecting too much? Or is there a setting I can try to totally prevent the grid being used on this single load or this time frame.
Thank you all in advance
G
Hi Everyone
It’s been a while and I’m still not much nearer resolving the 2 issues I still have Mainly regarding the load being taken from the grid instead of the battery pack above 2,5KW
And still not back on line with the WIFI dongle problem where the inverter can’t be seen online by me, or Sunsynk.
With regards the battery issue,
We have made some progress, anything above 2.5Kw load was being taken from the grid so the battery pack was being throttled to 2.5Kw.
I’m running a 5.5Kw inverter with 6Kw solar, and 6x Sunsynk 5.12 Batteries I dont export.
The problem is that the 3rd Slave Battery ‘seems’ to have a different firmware version than the others, so it’s killing the communication and making the inverter ‘see’ only one battery instead of 6 so when batteries are needed its limiting the discharge to 50A even though there is 30KW of storage regardless of the settings I use in the inverter battery section.
We have therefore temporarily by-passed Slave no3 and the inverter is now seeing 5 batteries and no longer pulling from the grid above 2.5Kw
However, since then the communication between the batteries and inverter is now down, all I get now is the screen full of Zero’s in the LiBMS part of the display, and we’ve tried everything changing cables etc, even reducing the connected batteries to a single one to try and kick-start the comms but nothing is working as yet all i can get is the Zeros’ (no communication screen)
So if anyone has had a similar problem with comms I would appreciate any input at this point as I’m running out of Ideas.
Also, if anyone has done a firmware update on the 5.12 Batteries, again I would appreciate some help, I’m OK with software and Serial cable comms but there seems to be conflicting info online as to which boot logger program and pin connections for the cable to use
These batteries have a CAN port and an RS232 Serial port only, (not the RS485)
So again if anyone has done this firmware update, any help will be much appreciated
I’m not sure if one battery needs doing to match the other 5, or the other 5 to match the odd one out if you follow, so maybe flash all 6 the same and see how we get on
With regards to the WIFI connection problem
after 3 weeks The technical dept came back with a diagnosis of faulty WI FI board, So they are going to send me a replacement board (its only a very small easy to swap board where the dongle plugs in) which we will fit and hopefully this will solve the connection problem
Il report back when done if it works in case anyone else has a similar issue, I’ve been off line for over 4 weeks now and losing control of the inverter’s daily timer settings
Any help with the Battery firmware, and LiBMS communication problem will be great
G