diff --git a/README.md b/README.md
index 5b457972..3804c235 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,7 @@ The following PowerShell scripts can be found in the `Scripts/` subfolder:
 * [SHA256.ps1](Scripts/SHA256.ps1) - prints the SHA256 checksum of the given file
 * [simulate-presence.ps1](Scripts/simulate-presence.ps1) - simulates the human presence against burglars
 * [speak.ps1](Scripts/speak.ps1) - speaks the given text by text-to-speech (TTS)
+* [switch-shelly1.ps1](Scripts/switch-shelly1.ps1) - switches a Shelly1 device in the local network
 * [take-screenshot.ps1](Scripts/take-screenshot.ps1) - takes a single screenshot
 * [take-screenshots.ps1](Scripts/take-screenshots.ps1) - takes multiple screenshots
 * [test.ps1](Scripts/test.ps1) - simple test script
diff --git a/Scripts/simulate-presence.ps1 b/Scripts/simulate-presence.ps1
old mode 100644
new mode 100755
diff --git a/Scripts/switch-shelly1.ps1 b/Scripts/switch-shelly1.ps1
new file mode 100755
index 00000000..6d2fc383
--- /dev/null
+++ b/Scripts/switch-shelly1.ps1
@@ -0,0 +1,27 @@
+#!/snap/bin/powershell
+
+# Syntax:       ./switch-shelly1.ps1 [<IP addr>] [<turn mode>] [<timer>]
+# Description:	switches a Shelly1 device in the local network
+# Author:	Markus Fleschutz
+# Source:	github.com/fleschutz/PowerShell
+# License:	CC0
+
+param([string]$IPaddr, [string]$TurnMode, [int]$Timer)
+if ($IPaddr -eq "" ) {
+	$IPaddr = read-host "Enter IP address of Shelly1 device"
+}
+if ($TurnMode -eq "" ) {
+	$TurnMode = read-host "Enter turn mode (on/off/toggle)"
+}
+if ($Timer -eq 0 ) {
+	$Timer = read-host "Enter timer (0=endless)"
+}
+
+try {
+	$URL = "http://$($IPaddr)/relay/0?turn=$($TurnMode)&timer=$($Timer)"
+	$result = Invoke-RestMethod $URL
+
+	write-host "OK - switched Shelly1 device at $IPaddr to $TurnMode for $Timer second(s)"
+	exit 0
+} catch { Write-Error $Error[0] }
+exit 1