Instruction manuals

STH-300MA

Extension box with timer

1. 1

   Power connection

   Plug the unit into a 3-pin socket. The OLED display turns on automatically.

2. 2

   Set the clock

   Check the time on the OLED screen. To change it, press and hold OK for 5 seconds, then release. Set the hour with H1 and the minutes with M1, then press OK.

3. 3

   Choose a mode

   Use the power switch: Manual mode is normal operation without the timer; Auto mode switches each socket on and off by its timers, every day.

4. 4

   Set the timers (Auto mode)

   Press Mode to select SCK1. Set the start time with H1 and M1 and the stop time with H2 and M2 (24-hour format), then press OK. Each socket has up to 3 time ranges. Press Mode repeatedly to move to SK2 and SK3 and repeat.

Important notes

• Always confirm timer settings by pressing OK.
• Set unused timers to 00:00 – 00:00 to prevent unintended switching.
• To reset all timers, press and hold Mode for 5 seconds.
• Keep the unit connected to a stable power source for reliable operation.

STH-400AC

Smart extension power board

1. 1

   Plug in

   Plug in the power cable.

2. 2

   Choose a mode

   The first button from the left is the MODE button. Short-press it to switch between Manual mode (LED glows continuously), Auto mode (LED blinks) and Off mode.

3. 3

   Connect the app

   In Auto mode a fast blink means the board is ready to pair on the same Wi-Fi network; a slow blink means it is paired. Press and hold MODE for 10 seconds to connect or disconnect a paired device.

4. 4

   Control and automate

   In Auto mode, operate the board online with the Simmang Tech app over 2.4 GHz Wi-Fi, or schedule custom automation for all 4 sockets individually.

Get the Simmang Tech app for Android or iOS.