[Plant Consumed] Calculated power is negative - DCEV discharging

[purcell-lab]

When using the DCEV charger for discharging the calculated plant consumed power is negative.

This error originated from a custom integration.

Logger: custom_components.sigen.calculated_sensor
Source: custom_components/sigen/calculated_sensor.py:347
integration: Sigenergy ESS (documentation, issues)
First occurred: 09:07:43 (48 occurrences)
Last logged: 11:15:39

[CS][Plant Consumed] Calculated power is negative: -5.66 kW = 6.049 + 0 - 16.026 - -4.317
[CS][Plant Consumed] Calculated power is negative: -5.583999999999998 kW = 6.117 + 0 - 16.019 - -4.318
[CS][Plant Consumed] Calculated power is negative: -5.619999999999999 kW = 6.084 + 0 - 16.022 - -4.318
[CS][Plant Consumed] Calculated power is negative: -5.565999999999999 kW = 6.128 + 0 - 16.011 - -4.317
[CS][Plant Consumed] Calculated power is negative: -5.529000000000001 kW = 6.17 + 0 - 16.015 - -4.316

[TypQxQ]

Thank you. I will look into this when I get back from vacation.

[frver]

I have the same problem. I don't have a DC charger. Just PV + Battery.
Probably the double minus is not parsed properly (- - 0.004) which is the battery power.

Maybe this helps to resolve.

Logger: custom_components.sigen.calculated_sensor
Bron: custom_components/sigen/calculated_sensor.py:347
integratie: Sigenergy ESS (documentatie, problemen)
Eerst voorgekomen: 13:13:18 (169 gebeurtenissen)
Laatst gelogd: 13:54:16

[CS][Plant Consumed] Calculated power is negative: -4.475586568020162e-16 kW = 7.512 + 0 - 7.516 - -0.004
[CS][Plant Consumed] Calculated power is negative: -4.475586568020162e-16 kW = 7.593 + 0 - 7.597 - -0.004
[CS][Plant Consumed] Calculated power is negative: -4.475586568020162e-16 kW = 7.808 + 0 - 7.812 - -0.004
[CS][Plant Consumed] Calculated power is negative: -1.3357370765021415e-15 kW = 9.626 + 0 - 9.63 - -0.004
[CS][Plant Consumed] Calculated power is negative: -1.3357370765021415e-15 kW = 12.447 + 0 - 12.451 - -0.004

[purcell-lab]

This issue persists with v1.0.10 when discharging from the EVDC charger. The -12.5 kW values below is the output from the DCEV charger.

This error originated from a custom integration.

Logger: custom_components.sigen.calculated_sensor
Source: custom_components/sigen/calculated_sensor.py:379
integration: Sigenergy ESS (documentation, issues)
First occurred: 17 July 2025 at 20:32:07 (1604 occurrences)
Last logged: 07:22:19

[CS][Plant Consumed] Calculated power is negative: -12.479 kW = 0.0 + 0 - 12.578 - -0.099
[CS][Plant Consumed] Calculated power is negative: -12.476 kW = 0.0 + 0 - 12.579 - -0.103
[CS][Plant Consumed] Calculated power is negative: -12.479 kW = 0.0 + 0 - 12.581 - -0.102
[CS][Plant Consumed] Calculated power is negative: -12.482000000000001 kW = 0.0 + 0 - 12.579 - -0.097
[CS][Plant Consumed] Calculated power is negative: -12.482 kW = 0.0 + 0 - 12.581 - -0.099

[TypQxQ]

Hi @purcell-lab, @frver and anyone wanting to try the new fix!
I remade the calculation to add any chargers but can't test it as I have no charger.

I also rewrote a bit on the DC Charger code to remove some overhead and I don't know if it's working all right now.

Could you please try out the new https://github.com/TypQxQ/Sigenergy-Local-Modbus/tree/Dev.1.0.11 Dev branch to see if it works.
Thank you!

/Andrei

[frver]

Hi @TypQxQ /Andrei,

I don't have a charger. This problem is also visible with just PV and a Battery.
I'm on 1.0.10.

Looked into the code and your changes, but I suspect it will not resolve the issue I encountered (as I don't have any chargers or anything else than 1 hybrid inverter connected to 3 8kWh batteries)
-0.45999999999999963 kW = 6.82 + 0 - 7.287 - -0.007
pv_power + grid_import - grid_export - battery_power

I was thinking it may be related to the issue pv_power from the inverter gives a different value than from the plant. It is in the order of magnitude I'm seeing. See also: #83
In contrast to what I responded in that discussion, I see a delta between both values both positive and negative. So I think the problem I was seeing is more likely to originate from how Sigenergy calculates the PV power than any issue with the integration.
Attached below a graph of the delta between the Plant PV power and the Inverter PV power. You can see it both goes positive and negative.

It maybe related to adding up values taken from different timestamps (either through modbus or already inside the inverter itself)