Power variable calc updates, new method for Huawei

- Added output current as new `UPS_Value`
- Renamed a few `PowerMethod` enums to be more descriptive of what they do
- Trying a new well-known variable initialization method that utilizes nullable values. Variable is left null if there's a problem retrieving it from the NUT server, then it will not be updated in the future. Only applying this to `output.current` since its use is limited to power calculation only. Applying this to other variables will likely require greater structural changes throughout WinNUT.
- Added power calculation method involving output voltage and current, doable in a Huawei UPS (see #150)
- GetUPSVar no longer prints a line assuming that the raised exception will go unhandled if a fallback value was not provided.

Author: gbakeman

WinNUT_V2/WinNUT-Client_Common/Common_Classes.vb

@@ -16,6 +16,7 @@ Public Class UPS_Values
     Public Batt_Runtime As Double = Nothing
     Public Input_Voltage As Double = Nothing
     Public Output_Voltage As Double = Nothing
+    Public Output_Current As Single?
     Public Power_Frequency As Double = Nothing
     Public Load As Double = Nothing
     Public Output_Power As Double = Nothing

WinNUT_V2/WinNUT-Client_Common/Common_Enums.vb

@@ -118,9 +118,13 @@ Public Enum UPS_States
     ALARM = 1 << 13
 End Enum
 
+''' <summary>
+''' Ref. https://github.com/nutdotnet/WinNUT-Client/pull/112
+''' </summary>
 Public Enum PowerMethod
     Unavailable ' No methods are available to calculate power.
     RealPower ' The ups.realpower variable is available for direct reading.
-    NominalPowerCalc ' Power can be calculated by taking the load percentage of the nominal power variable.
-    VoltAmpCalc ' Power will have be calculated as a function of volts and amps.
+    RPNomLoadPct ' Power is calcualted as the load percentage of nominal realpower.
+    InputNomVALoadPct ' Power is given as the nominal power calculated from nominal input volts/amps (and PF), multiplied by the percent load.
+    OutputVACalc ' Power is calculated with output voltage and current (seen on Huawei, issue #150)
 End Enum

WinNUT_V2/WinNUT-Client_Common/UPS_Device.vb

@@ -13,7 +13,7 @@ Imports System.Windows.Forms
 Public Class UPS_Device
 #Region "Statics/Defaults"
     Private ReadOnly INVARIANT_CULTURE = CultureInfo.InvariantCulture
-    Private Const CosPhi As Double = 0.6
+    Private Const POWER_FACTOR = 0.8
 
     ' How many milliseconds to wait before the Reconnect routine tries again.
     Private Const DEFAULT_RECONNECT_WAIT_MS As Double = 5000
@@ -238,27 +238,57 @@ Public Class UPS_Device
             Trim(GetUPSVar("ups.serial", "Unknown")),
             Trim(GetUPSVar("ups.firmware", "Unknown")))
 
+        With freshData.UPS_Value
+            LogFile.LogTracing("Initializing other well-known UPS variables...", LogLvl.LOG_DEBUG, Me)
+            Try
+                Dim value = Single.Parse(GetUPSVar("output.current"), INVARIANT_CULTURE)
+                .Output_Current = value
+                LogFile.LogTracing("output.current: " & value, LogLvl.LOG_DEBUG, Me)
+            Catch ex As Exception
+                If ex.GetType() <> GetType(NutException) Then
+                    LogFile.LogException(ex, Me)
+                End If
+            End Try
+            Try
+                Dim value = Single.Parse(GetUPSVar("output.voltage"), INVARIANT_CULTURE)
+                .Output_Voltage = value
+                LogFile.LogTracing("output.voltage: " & value, LogLvl.LOG_DEBUG, Me)
+            Catch ex As Exception
+                If ex.GetType() <> GetType(NutException) Then
+                    LogFile.LogException(ex, Me)
+                End If
+            End Try
+        End With
+
+        ' Determine optimal method for measuring power output from the UPS.
         LogFile.LogTracing("Determining best method to calculate power usage...", LogLvl.LOG_NOTICE, Me)
+        ' Start with directly reading a variable from the UPS.
         Try
             GetUPSVar("ups.realpower")
             _PowerCalculationMethod = PowerMethod.RealPower
-            LogFile.LogTracing("Using RealPower method to calculate power usage.", LogLvl.LOG_NOTICE, Me)
+            LogFile.LogTracing("Using RealPower method.", LogLvl.LOG_NOTICE, Me)
         Catch
             Try
                 GetUPSVar("ups.realpower.nominal")
                 GetUPSVar("ups.load")
-                _PowerCalculationMethod = PowerMethod.NominalPowerCalc
-                LogFile.LogTracing("Using NominalPowerCalc method to calculate power usage.", LogLvl.LOG_NOTICE, Me)
+                _PowerCalculationMethod = PowerMethod.RPNomLoadPct
+                LogFile.LogTracing("Using RPNomLoadPct method.", LogLvl.LOG_NOTICE, Me)
             Catch
                 Try
                     GetUPSVar("input.current.nominal")
                     GetUPSVar("input.voltage.nominal")
                     GetUPSVar("ups.load")
-                    _PowerCalculationMethod = PowerMethod.VoltAmpCalc
-                    LogFile.LogTracing("Using VoltAmpCalc method to calculate power usage.", LogLvl.LOG_NOTICE, Me)
+                    _PowerCalculationMethod = PowerMethod.InputNomVALoadPct
+                    LogFile.LogTracing("Using InputNomVALoadPct method.", LogLvl.LOG_NOTICE, Me)
                 Catch
-                    _PowerCalculationMethod = PowerMethod.Unavailable
-                    LogFile.LogTracing("Unable to find a suitable method to calculate power usage.", LogLvl.LOG_WARNING, Me)
+                    If freshData.UPS_Value.Output_Current IsNot Nothing AndAlso
+                            freshData.UPS_Value.Output_Voltage <> Nothing Then
+                        _PowerCalculationMethod = PowerMethod.OutputVACalc
+                        LogFile.LogTracing("Using OutputVACalc method.", LogLvl.LOG_NOTICE, Me)
+                    Else
+                        _PowerCalculationMethod = PowerMethod.Unavailable
+                        LogFile.LogTracing("Unable to find a suitable method to calculate power usage.", LogLvl.LOG_WARNING, Me)
+                    End If
                 End Try
             End Try
         End Try
@@ -283,35 +313,43 @@ Public Class UPS_Device
                     .Batt_Charge = Double.Parse(GetUPSVar("battery.charge", -1), INVARIANT_CULTURE)
                     .Batt_Voltage = Double.Parse(GetUPSVar("battery.voltage", -1), INVARIANT_CULTURE)
                     .Batt_Runtime = Double.Parse(GetUPSVar("battery.runtime", -1), INVARIANT_CULTURE)
-                    .Power_Frequency = Double.Parse(GetUPSVar("input.frequency", Double.Parse(GetUPSVar("output.frequency", Freq_Fallback), INVARIANT_CULTURE)), INVARIANT_CULTURE)
+                    .Power_Frequency = Double.Parse(GetUPSVar("input.frequency", Freq_Fallback), INVARIANT_CULTURE)
                     .Input_Voltage = Double.Parse(GetUPSVar("input.voltage", -1), INVARIANT_CULTURE)
-                    .Output_Voltage = Double.Parse(GetUPSVar("output.voltage", .Input_Voltage), INVARIANT_CULTURE)
+                    .Output_Voltage = Double.Parse(GetUPSVar("output.voltage", -1), INVARIANT_CULTURE)
                     .Load = Double.Parse(GetUPSVar("ups.load", 0), INVARIANT_CULTURE)
 
                     ' Retrieve and/or calculate output power if possible.
                     If _PowerCalculationMethod <> PowerMethod.Unavailable Then
                         Dim parsedValue As Double
 
                         Try
-                            If _PowerCalculationMethod = PowerMethod.RealPower Then
-                                parsedValue = Double.Parse(GetUPSVar("ups.realpower"), INVARIANT_CULTURE)
-
-                            ElseIf _PowerCalculationMethod = PowerMethod.NominalPowerCalc Then
-                                parsedValue = Double.Parse(GetUPSVar("ups.realpower.nominal"), INVARIANT_CULTURE)
-                                parsedValue *= UPS_Datas.UPS_Value.Load / 100.0
-
-                            ElseIf _PowerCalculationMethod = PowerMethod.VoltAmpCalc Then
-                                Dim nomCurrent = Double.Parse(GetUPSVar("input.current.nominal"), INVARIANT_CULTURE)
-                                Dim nomVoltage = Double.Parse(GetUPSVar("input.voltage.nominal"), INVARIANT_CULTURE)
-
-                                parsedValue = (nomCurrent * nomVoltage * 0.8) * (UPS_Datas.UPS_Value.Load / 100.0)
-                            Else
-                                Throw New InvalidOperationException("Insufficient variables to calculate power.")
-                            End If
+                            Select Case _PowerCalculationMethod
+                                Case PowerMethod.RealPower
+                                    parsedValue = Double.Parse(GetUPSVar("ups.realpower"), INVARIANT_CULTURE)
+
+                                Case PowerMethod.RPNomLoadPct
+                                    parsedValue = Double.Parse(GetUPSVar("ups.realpower.nominal"), INVARIANT_CULTURE)
+                                    parsedValue *= UPS_Datas.UPS_Value.Load / 100.0
+
+                                Case PowerMethod.InputNomVALoadPct
+                                    Dim nomCurrent = Double.Parse(GetUPSVar("input.current.nominal"), INVARIANT_CULTURE)
+                                    Dim nomVoltage = Double.Parse(GetUPSVar("input.voltage.nominal"), INVARIANT_CULTURE)
+
+                                    parsedValue = nomCurrent * nomVoltage * POWER_FACTOR
+                                    parsedValue = UPS_Datas.UPS_Value.Load / 100.0
+                                Case PowerMethod.OutputVACalc
+                                    .Output_Current = Single.Parse(GetUPSVar("output.current"), INVARIANT_CULTURE)
+                                    parsedValue = .Output_Current * .Output_Voltage * POWER_FACTOR
+                                Case Else
+                                    ' Should not trigger - something has gone wrong.
+                                    Throw New InvalidOperationException("Insufficient variables to calculate power.")
+                            End Select
                         Catch ex As FormatException
                             LogFile.LogTracing("Unexpected format trying to parse value from UPS. Exception:", LogLvl.LOG_ERROR, Me)
                             LogFile.LogTracing(ex.ToString(), LogLvl.LOG_ERROR, Me)
                             LogFile.LogTracing("parsedValue: " & parsedValue, LogLvl.LOG_ERROR, Me)
+                        Catch ex As Exception
+                            LogFile.LogException(ex, Me)
                         End Try
 
                         .Output_Power = parsedValue
@@ -428,7 +466,6 @@ Public Class UPS_Device
                     LogFile.LogTracing("Apply Fallback Value when retrieving " & varName, LogLvl.LOG_WARNING, Me)
                     Return Fallback_value
                 Else
-                    LogFile.LogTracing("Unhandled error while getting " & varName, LogLvl.LOG_ERROR, Me)
                     Throw
                 End If
             End Try