Fix bug in AC input power calculation

Specific to AC inputs on Multi RS systems

data/common/ActiveAcInput.qml

@@ -27,22 +27,17 @@ Device {
 	readonly property AcInputPhaseModel _phases: AcInputPhaseModel {
 		id: _phases
 
-		property real totalPower: NaN
 		property real firstPhaseCurrent: NaN
+		readonly property int totalPower: {
+			let sum = 0
+			for (let i = 0; i < count; ++i) {
+				sum += get(i).power || 0
+			}
+			return sum
+		}
 
 		onPhaseValueChanged: function(phaseIndex, propertyName, propertyValue) {
-			if (propertyName === "power" && !root._acInputService.hasTotalPower) {
-				let total = NaN
-				for (let i = 0; i < phases.count; ++i) {
-					if (i === phaseIndex) {
-						total = Units.sumRealNumbers(total, propertyValue)
-					} else {
-						const phase = get(phaseIndex)
-						total = Units.sumRealNumbers(total, phase ? phase[propertyName] : NaN)
-					}
-				}
-				totalPower = total
-			} else if (propertyName === "current" && count === 1) {
+			if (propertyName === "current" && count === 1) {
 				firstPhaseCurrent = propertyValue
 			}
 		}