diff --git a/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt b/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt
index e092200..72a5b51 100644
--- a/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt
+++ b/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt
@@ -32,7 +32,7 @@
     this.axisLeft.setDrawGridLines(false) //设置x轴上每个点对应的线
     this.axisLeft.setDrawZeroLine(true)
     //添加限制线
-    val threshold = SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 1.99f) as Float
+    val threshold = SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 0.1f) as Float
     val limitLine = LimitLine(threshold, "阈值：${threshold}% VOL")
     limitLine.lineWidth = 1f
     limitLine.lineColor = Color.RED

diff --git a/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt b/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt
index e092200..72a5b51 100644
--- a/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt
+++ b/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt
@@ -32,7 +32,7 @@
     this.axisLeft.setDrawGridLines(false) //设置x轴上每个点对应的线
     this.axisLeft.setDrawZeroLine(true)
     //添加限制线
-    val threshold = SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 1.99f) as Float
+    val threshold = SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 0.1f) as Float
     val limitLine = LimitLine(threshold, "阈值：${threshold}% VOL")
     limitLine.lineWidth = 1f
     limitLine.lineColor = Color.RED
diff --git a/app/src/main/java/com/casic/app/safetreecontroller/fragments/MethaneMonitorFragment.kt b/app/src/main/java/com/casic/app/safetreecontroller/fragments/MethaneMonitorFragment.kt
index 4a86ca8..14794a4 100644
--- a/app/src/main/java/com/casic/app/safetreecontroller/fragments/MethaneMonitorFragment.kt
+++ b/app/src/main/java/com/casic/app/safetreecontroller/fragments/MethaneMonitorFragment.kt
@@ -111,8 +111,8 @@
         binding.updateThresholdButton.setOnClickListener {
             //更新甲烷阈值
             val threshold = binding.thresholdView.text.toString().toFloat()
-            if (threshold >= 20f) {
-                "报警阈值不能超过20% VOL".show(requireContext())
+            if (threshold > 1f) {
+                "报警阈值不能超过1%VOL".show(requireContext())
                 return@setOnClickListener
             }
 
@@ -122,8 +122,8 @@
                 ?: return@setOnClickListener
             val message = weakReferenceHandler.obtainMessage()
             message.what = LocaleConstant.UPDATE_GAS_THRESHOLD_CODE
-            //用户使用 % VOL，但是单片机只能设置ppm`m，所以需要转换一下
-            message.obj = (threshold * 500).toInt()
+            //用户使用【%VOL】，但是单片机只能设置【ppm·m】，所以需要转换一下
+            message.obj = (threshold * 10000).toInt()
             weakReferenceHandler.sendMessage(message)
         }
 
@@ -161,9 +161,9 @@
             LocaleConstant.QUERY_METHANE_RESPONSE_CODE -> {
                 val ppm = msg.obj as Long
                 //LEL百分比 = (X / 10000) / 0.05 × 100% = X / 500
-                val formatValue = "%.2f".format(ppm / 500f)
+                val formatValue = "%.2f".format(ppm / 10000f)
                 binding.currentGasValueView.text = "当前燃气浓度：${formatValue}% VOL"
-                if (ppm > binding.thresholdView.text.toString().toFloat() * 500) {
+                if (ppm > binding.thresholdView.text.toString().toFloat() * 10000) {
                     binding.currentGasValueView.setTextColor(Color.RED)
                     binding.currentGasValueView.typeface = Typeface.DEFAULT_BOLD
                 } else {
@@ -204,7 +204,8 @@
         }
 
         //回显甲烷默认阈值
-        val value = SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 1.99f) as Float
-        binding.thresholdView.setText(value.toString())
+        val threshold =
+            SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 0.1f) as Float
+        binding.thresholdView.setText(threshold.toString())
     }
 }
\ No newline at end of file

diff --git a/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt b/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt
index e092200..72a5b51 100644
--- a/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt
+++ b/app/src/main/java/com/casic/app/safetreecontroller/extensions/LineChart.kt
@@ -32,7 +32,7 @@
     this.axisLeft.setDrawGridLines(false) //设置x轴上每个点对应的线
     this.axisLeft.setDrawZeroLine(true)
     //添加限制线
-    val threshold = SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 1.99f) as Float
+    val threshold = SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 0.1f) as Float
     val limitLine = LimitLine(threshold, "阈值：${threshold}% VOL")
     limitLine.lineWidth = 1f
     limitLine.lineColor = Color.RED
diff --git a/app/src/main/java/com/casic/app/safetreecontroller/fragments/MethaneMonitorFragment.kt b/app/src/main/java/com/casic/app/safetreecontroller/fragments/MethaneMonitorFragment.kt
index 4a86ca8..14794a4 100644
--- a/app/src/main/java/com/casic/app/safetreecontroller/fragments/MethaneMonitorFragment.kt
+++ b/app/src/main/java/com/casic/app/safetreecontroller/fragments/MethaneMonitorFragment.kt
@@ -111,8 +111,8 @@
         binding.updateThresholdButton.setOnClickListener {
             //更新甲烷阈值
             val threshold = binding.thresholdView.text.toString().toFloat()
-            if (threshold >= 20f) {
-                "报警阈值不能超过20% VOL".show(requireContext())
+            if (threshold > 1f) {
+                "报警阈值不能超过1%VOL".show(requireContext())
                 return@setOnClickListener
             }
 
@@ -122,8 +122,8 @@
                 ?: return@setOnClickListener
             val message = weakReferenceHandler.obtainMessage()
             message.what = LocaleConstant.UPDATE_GAS_THRESHOLD_CODE
-            //用户使用 % VOL，但是单片机只能设置ppm`m，所以需要转换一下
-            message.obj = (threshold * 500).toInt()
+            //用户使用【%VOL】，但是单片机只能设置【ppm·m】，所以需要转换一下
+            message.obj = (threshold * 10000).toInt()
             weakReferenceHandler.sendMessage(message)
         }
 
@@ -161,9 +161,9 @@
             LocaleConstant.QUERY_METHANE_RESPONSE_CODE -> {
                 val ppm = msg.obj as Long
                 //LEL百分比 = (X / 10000) / 0.05 × 100% = X / 500
-                val formatValue = "%.2f".format(ppm / 500f)
+                val formatValue = "%.2f".format(ppm / 10000f)
                 binding.currentGasValueView.text = "当前燃气浓度：${formatValue}% VOL"
-                if (ppm > binding.thresholdView.text.toString().toFloat() * 500) {
+                if (ppm > binding.thresholdView.text.toString().toFloat() * 10000) {
                     binding.currentGasValueView.setTextColor(Color.RED)
                     binding.currentGasValueView.typeface = Typeface.DEFAULT_BOLD
                 } else {
@@ -204,7 +204,8 @@
         }
 
         //回显甲烷默认阈值
-        val value = SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 1.99f) as Float
-        binding.thresholdView.setText(value.toString())
+        val threshold =
+            SaveKeyValues.getValue(LocaleConstant.METHANE_DEFAULT_VALUE_KEY, 0.1f) as Float
+        binding.thresholdView.setText(threshold.toString())
     }
 }
\ No newline at end of file
diff --git a/app/src/main/res/layout/fragment_methane_monitor.xml b/app/src/main/res/layout/fragment_methane_monitor.xml
index 64c1b6c..376f43c 100644
--- a/app/src/main/res/layout/fragment_methane_monitor.xml
+++ b/app/src/main/res/layout/fragment_methane_monitor.xml
@@ -76,7 +76,7 @@
                 android:maxLength="4"
                 android:padding="@dimen/dp_5"
                 android:singleLine="true"
-                android:text="1.99"
+                android:text="0.1"
                 android:textColor="@color/black"
                 android:textSize="@dimen/sp_16" />