Unexplained energy consumption and other questions

Other languages
1

Hello everyone.

I have been operating an off-grid system for my house construction for several months.
4 PV 300WP 2S2P
SmartSolar Charger MPPT 150/45 v1.64
Colour Control GX. v3.51
MultiPlus-II 48/5000/70-48. v552
8 pieces Pytes E-Box-48100R-C 5.12 kWh = approx. 40kWh
Controlled via Pytes BMS

My consumption has been 0.3 to 3kWh per day for a long time.

Everything went well until 14.11.2024, then there was an inexplicable discharge from 86% SOC to 10% SOC within 2.5 hours, i.e. approx. 30kWh.
But my consumption was at most 3kWh.
The consumption indicated in the dashboard for the entire day was 1.0 kWh.
There was the following alarm: Battery Monitor - Pytes - Internal Failure: Alarm

I have thought about short circuits or damage to the extension cables but have not yet been able to find a fault.
So I don’t know where the 30kWh ‘disappeared’ to.

From 15.11.2024 I ran a generator on AC Input 1 every day and after 3 days with little PV yield I am back to 72% SOC.

While the generator is running, I notice a consumption of 0.5 kW per hour of running time, although I only have approx. 20 watts of load connected to it.

I’m quite at a loss as to what could have happened?

Could the energy have been lost internally in the batteries?

I still have a separate question:
Since I’ve been using the Pytes (previously Pylontech), the dashboard shows another field next to the battery, labelled DC Power, which is connected to the battery and shows both positive and negative currents up to approx. 0 to 8A, which change every second. Are these balancing currents between the individual bytes?

Thanks for any help.

2

You’ve activated in the CCGX’s menu “Had DC system”. Settings → System Setup → Has DC system.
Those are the currents that are not accounted for in the DC side.
For example if you have a device that is directly drawing power from the battery.
Are calculated values and are not always so exact.
In other words, “Power in” must be equal with “Power out”. Any difference is shown there.
For example is a good way of calculating the power loss / efficiency of the system, as there you can find the unaccounted values.
For example, in your case, from 172W of PV power, 21W are lost (DC power) and about 150W reach the battery.

3

Ah, thank you, that makes sense now.

Do you also have an idea, how I could loose 30Kwh within only 2.5 hours?

4

Probably a problem with the batteries, hence the alarm.
To be sure is no other problem, just browse through the various widgets and see if it’s anything abnormal there.