Quick start
- 1Prepare MP3 audio files
- 2Copy files to the USB root directory
- 3Insert the USB drive into the LC-308S
- 4Connect the bell through the timer
- 5Select the required starting track
- 6Lower the volume, then test and adjust
- 7Program the timer schedule
- 8Set the timer to AUTO and test every event
Product overview
The LC-308S plays MP3 audio stored on a USB flash drive. A connected timer determines when the bell receives power; the bell determines which track plays.
Use custom bell sounds, music or recorded announcements for schools, factories, warehouses and offices. The music-select control advances through the available tracks, while the volume control sets the output level.
- MP3 playback from USB flash drive
- Sequential track playback with automatic looping
- Adjustable volume and track selection
- Compatible with external programmable timer control
Dimensions
Plan a dry, secure wall position that remains accessible for USB replacement and volume adjustment.
| Spec | Value |
|---|---|
| Width | 260 mm |
| Height | 180 mm |
| Depth | 120 mm |
| Rated power | ≤10 W |
Basic connection diagram
The timer acts as the automatic switch between the supply and the music bell.
Electrical work must be carried out safely
Disconnect power before wiring. Check the voltage on the product label. AC mains wiring can cause serious electric shock; use a qualified electrician if you are not trained to perform the installation.
USB music playback mode
With several MP3 files on the drive, each activation advances to the next track. After the final track, the sequence starts again.
| Activation | Track |
|---|---|
| 1st activation | Track 1 |
| 2nd activation | Track 2 |
| 3rd activation | Track 3 |
Need the same sound every time?
Keep only one MP3 file on the USB drive. This avoids relying on a multi-track sequence.
Wiring multiple bells
A single timer may activate several LC-308S bells on the same schedule when the timer, switching device, cable and total electrical load are correctly rated.
This arrangement is useful across school blocks, factory areas, warehouses or multiple floors. Do not connect additional bells until a qualified installer confirms the timer contacts and circuit can safely handle the combined load.
USB music selection flow
Prepare the drive carefully so the required track order remains easy to test and maintain.
Prepare the USB drive
- Use MP3 audio files.
- Place files in the root directory, not inside folders.
- Arrange and copy files in the required playback order.
- Safely eject the drive before inserting it into the bell.
Select the starting track
- Insert the USB drive and power on.
- Press the Music Select button.
- Continue pressing to hear the next available track.
- Stop when the required starting track is selected.
Keep a backup of all bell audio
Avoid removing the USB drive while audio is playing. If the order is wrong, delete the files and copy them to the drive again in the intended sequence.
System example — school bell
The timer schedule and the USB track order must match. Test the entire day’s sequence after any schedule or audio change.
| Timer event | USB track | Purpose |
|---|---|---|
| 08:00 | Track 1 | Morning assembly |
| 10:00 | Track 2 | Start recess |
| 12:30 | Track 3 | Lunch |
| 17:00 | Track 4 | End of school |
Safety
Work through the power, timer, USB and audio checks in that order if the bell misbehaves — see Troubleshooting below.
Stop and disconnect power
if the unit, cable or plug is damaged, unusually hot, wet, sparking or producing a burning smell. Do not open or service the powered unit.
Watch it in action
Troubleshooting
Bell does not turn on
Check the supply, wiring, timer output and AUTO/MANUAL status. Confirm the timer is currently supplying power.
USB music does not play
Reinsert the USB drive, confirm the files are MP3, place them in the root directory and try another compatible flash drive.
Wrong track or sequence
Use Music Select to find the starting track. If needed, erase the drive and copy the files again in the intended order.
No sound or low volume
Lower the volume before testing, activate the bell, then increase it gradually. Confirm the MP3 itself contains audible sound.
Timer works but bell does not play
Test the bell independently to isolate whether the issue is the timer, wiring, supply, USB drive or bell.
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