Modbus sunspec reads negative values for Voltage from phase to phase

Tags: #<Tag:0x00007f616f90afd8> #<Tag:0x00007f616f90af10> #<Tag:0x00007f616f90ad80>

today I checked out the new modbus sunspec function, to replace my old modbus readings and get rid of my calculation rules.
But I have a few problems.

For the inverter:
I get wrong readings for the phase to phase voltage.
I expect around 400V, but I get only 0V.
I get no temperature values.

For the power meter:
I get also wrong readings for the phase to phase voltage.
But here I get around -250V.
I get no reactive energy values.

Some ideas?

Many thanks in advance.

Used hardware:
Inverter: Solaredge SE7K
Powermeter: Solaredge branded WattNode WND-3Y-400-MB


Bridge  modbus:tcp:bridge [ host="", port=40, id=1, enableDiscovery=true ] {
        Thing   inverter-three-phase    40069   "SolarEdge SE7K"                [ address=40069, length=52, refresh=15 ]
        Thing   meter-wye-phase         40188   "WattNode WND-3Y-400-MB"        [ address=40188, length=107, refresh=15 ]

Part of inverter item file:

Number:ElectricPotential    se7k_VoltAB             "WR Spannung Ph. A-B [%.1f V]"                  (se7k)      { channel="modbus:inverter-three-phase:bridge:40069:acPhaseA#ac-voltage-to-next" }

Number:ElectricPotential    se7k_VoltBC             "WR Spannung Ph. B-C [%.1f V]"                  (se7k)      { channel="modbus:inverter-three-phase:bridge:40069:acPhaseB#ac-voltage-to-next" }

Number:ElectricPotential    se7k_VoltCA             "WR Spannung Ph. C-A [%.1f V]"                  (se7k)      { channel="modbus:inverter-three-phase:bridge:40069:acPhaseC#ac-voltage-to-next" }

// Cabinet Temperature
Number:Temperature          se7k_CT                 "WR Temperatur Gehäuse [%.2f C]"                (se7k)      { channel="modbus:inverter-three-phase:bridge:40069:deviceInformation#cabinet-temperature" }

// Heat Sink Temperature
Number:Temperature          se7k_HST                "WR Temperatur Kühlkorper [%.2f C]"             (se7k)      { channel="modbus:inverter-three-phase:bridge:40069:deviceInformation#heatsink-temperature" }

// Transformer Temperature
Number:Temperature          se7k_TT                 "WR Temperatur Transformer [%.2f C]"            (se7k)      { channel="modbus:inverter-three-phase:bridge:40069:deviceInformation#transformer-temperature" }

// Other Temperature
Number:Temperature          se7k_OT                 "WR Temperatur Other [%.2f C]"                  (se7k)      { channel="modbus:inverter-three-phase:bridge:40069:deviceInformation#other-temperature" }

Part of power meter item file:

Number:ElectricPotential    se7km_VoltLL                "SM Spannung L-L (MW alle Phasen) [%.2f V]"                                 (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acGeneral#ac-average-voltage-to-next" }

Number:ElectricPotential    se7km_VoltAB                "SM Spannung Ph.A-B [%.2f V]"                                               (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseA#ac-voltage-to-next" }

Number:ElectricPotential    se7km_VoltBC                "SM Spannung Ph.B-C [%.2f V]"                                               (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseB#ac-voltage-to-next" }

Number:ElectricPotential    se7km_VoltCA                "SM Spannung Ph.C-A [%.2f V]"                                               (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseC#ac-voltage-to-next" }

Number:Energy               se7km_VARhQ1                "SM Bezugszähler Q1 reaktive Energie (Summe alle Phasen) [%.2f kVARh]"      (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acGeneral#ac-total-imported-reactive-energy-q1" }

Number:Energy               se7km_VARhQ1A               "SM Bezugszähler Q1 reaktive Energie Ph.A [%.2f kVARh]"                     (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseA#ac-imported-reactive-energy-q1" }

Number:Energy               se7km_VARhQ1B               "SM Bezugszähler Q1 reaktive Energie Ph.B [%.2f kVARh]"                     (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseB#ac-imported-reactive-energy-q1" }

Number:Energy               se7km_VARhQ1C               "SM Bezugszähler Q1 reaktive Energie Ph.C [%.2f kVARh]"                     (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseC#ac-imported-reactive-energy-q1" }

Number:Energy               se7km_VARhQ2                "SM Bezugszähler Q2 reaktive Energie (Summe alle Phasen) [%.2f kVARh]"      (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acGeneral#ac-total-imported-reactive-energy-q2" }

Number:Energy               se7km_VARhQ2A               "SM Bezugszähler Q2 reaktive Energie Ph.A [%.2f kVARh]"                     (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseA#ac-imported-reactive-energy-q2" }

Number:Energy               se7km_VARhQ2B               "SM Bezugszähler Q2 reaktive Energie Ph.B [%.2f kVARh]"                     (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseB#ac-imported-reactive-energy-q2" }

Number:Energy               se7km_VARhQ2C               "SM Bezugszähler Q2 reaktive Energie Ph.C [%.2f kVARh]"                     (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseC#ac-imported-reactive-energy-q2" }

Number:Energy               se7km_VARhQ3                "SM Einpeisezähler Q3 reaktive Energie (Summe alle Phasen) [%.2f kVARh]"    (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acGeneral#ac-total-exported-reactive-energy-q3" }

Number:Energy               se7km_VARhQ3A               "SM Einpeisezähler Q3 reaktive Energie Ph.A [%.2f kVARh]"                   (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseA#ac-exported-reactive-energy-q3" }

Number:Energy               se7km_VARhQ3B               "SM Einpeisezähler Q3 reaktive Energie Ph.B [%.2f kVARh]"                   (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseB#ac-exported-reactive-energy-q3" }

Number:Energy               se7km_VARhQ3C               "SM Einpeisezähler Q3 reaktive Energie Ph.C [%.2f kVARh]"                   (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseC#ac-exported-reactive-energy-q3" }

Number:Energy               se7km_VARhQ4                "SM Einpeisezähler Q4 reaktive Energie (Summe alle Phasen) [%.2f kVARh]"    (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acGeneral#ac-total-exported-reactive-energy-q4" }

Number:Energy               se7km_VARhQ4A               "SM Einpeisezähler Q4 reaktive Energie Ph.A [%.2f kVARh]"                   (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseA#ac-exported-reactive-energy-q4" }

Number:Energy               se7km_VARhQ4B               "SM Einpeisezähler Q4 reaktive Energie Ph.B [%.2f kVARh]"                   (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseB#ac-exported-reactive-energy-q4" }

Number:Energy               se7km_VARhQ4C               "SM Einpeisezähler Q4 reaktive Energie Ph.C [%.2f kVARh]"                   (se7km)     { channel="modbus:meter-wye-phase:bridge:40188:acPhaseC#ac-exported-reactive-energy-q4" }

Maybe @mrbig is the right one to ask for help, as he just fixed my issue a few days ago ([SOLVED] Wrong Values with Modbus and KOSTAL Smart Energy Meter)

@SMHRambo, do you have a modbus specification of the inverter used? Maybe this supports the fixing.


Hello @SMHRambo,

can you please post a screenshot of the paperui showing the inverter values (possibly when it’s producing power)?

Please note, that this binding will expose all the items specified by the specification. However not all fields are mandatory, and several devices do not implement all of them.

Unsupported items usually are marked with NaN, but it’s also ok, to display 0. (For example the Phase to Phase Voltage might not be reported)

Also my SE4000 only reports heatsink temperature, but not the others.

Negative phase-to-phase voltages could be correct, this is kind of a notational thing.

To be able to answer the case more effectively you could turn on the communication debugging like described here If you attach the output of the modbus communcation I can look into it in more detail, to see if the device does not report the missing values, or if there is a problem in the binding.

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