diff --git a/applets/systemmonitor/common/contents/ui/ConfigGeneral.qml b/applets/systemmonitor/common/contents/ui/ConfigGeneral.qml
--- a/applets/systemmonitor/common/contents/ui/ConfigGeneral.qml
+++ b/applets/systemmonitor/common/contents/ui/ConfigGeneral.qml
@@ -126,15 +126,14 @@
             to: 1000000
             editable: true
             validator: DoubleValidator {
-                bottom: spinbox.from
-                top: spinbox.to
+                bottom: updateIntervalSpinBox.from
+                top: updateIntervalSpinBox.to
             }
-            textFromValue: function(value) {
-                var seconds = value / 1000
-                return i18ncp("SpinBox text", "%1 second", "%1 seconds", seconds.toFixed(1))
+            textFromValue: function(value, locale) {
+                return i18nc("Update interval", "%1 seconds", Number(value / 1000).toLocaleString(locale, 'f', 1))
             }
-            valueFromText: function(text) {
-                return parseFloat(text) * 1000
+            valueFromText: function(text, locale) {
+                return Number.fromLocaleString(locale, text) * 1000
             }
             value: cfg_updateInterval
             onValueModified: cfg_updateInterval = value