1. Introduction
The SINOTIMER TM928S series is a versatile 7-day programmable digital timer switch designed for household and industrial applications. It features a backlight LCD display, precise second-interval programming, and DIN rail mounting for easy integration into electrical systems. This manual provides detailed instructions for the safe installation, operation, and maintenance of your timer switch.
Key Features:
- 16 ON/OFF setting programs per day/week
- LCD display with backlight for clear visibility
- Wide power supply range: 85-265VAC, 50/60Hz
- Manual ON/OFF/AUTO switching modes
- Built-in rechargeable battery for program memory retention (90 days black-out)
- Time setting includes hour, minute, and second, with weekly programming
- Lock function to prevent accidental changes
Figure 1: SINOTIMER TM928S Programmable Timer Switch (Front View)
2. Specifications
| Attribute | Value |
|---|---|
| Model Number | TM928SAKL (16A) / TM928SBKL (30A) |
| Brand Name | SINOTIMER |
| Theory | Digital |
| Type | Mini |
| Use | Timer Switch |
| Power Supply | 85-265VAC, 50/60HZ |
| Max. Current of Output Load | 16A (TM928SAKL) / 30A (TM928SBKL) |
| Programs | 16 ON/OFF per day |
| Mini Setting Interval | 1 second |
| Display | LCD Backlight |
| Power Consumption | <5VA |
| Black-out Memory | 90 days |
| Battery Included | Yes (TM928SAKL: Replaceable CR2032; TM928SBKL: Non-replaceable internal battery) |
| Dimensions | 86*65*36mm (approx. 8.7cm x 6.5cm x 3.6cm) |
| Installation | DIN RAIL (35mm) |
| Certification | CE |
Figure 2: Approximate Dimensions of the Timer Switch
3. Safety Information
WARNING: Risk of electric shock. Installation and servicing should only be performed by qualified personnel.
- Always disconnect power before installing or servicing the device.
- Ensure all wiring connections are secure and comply with local electrical codes.
- Do not exceed the maximum load current specified for your model (16A or 30A).
- Keep the device away from water and excessive moisture.
- Do not attempt to open or repair the device yourself, especially the TM928SBKL model with its non-replaceable internal battery.
4. Installation
4.1 Mounting
The SINOTIMER TM928S series timer switch is designed for 35mm DIN rail mounting. Simply clip the device onto a standard DIN rail in your electrical panel.
Figure 3: Rear view showing DIN rail mounting mechanism
4.2 Wiring Diagrams
The wiring configuration depends on the model (16A or 30A) and whether a contactor is used for higher loads. Always ensure power is disconnected before wiring.
4.2.1 TM928SAKL (16A Model) Direct Load Wiring
For loads up to 16A, the timer can directly control the device. Connect the Line (L) and Neutral (N) to terminals 1 and 2 respectively for power supply. The load is connected between terminal 3 (NO - Normally Open) and the Neutral (N) line. Terminal 4 (NC - Normally Closed) is not used in this configuration.
Figure 4: Wiring for TM928SAKL (16A) Direct Load
4.2.2 TM928SAKL (16A Model) with Contactor
For inductive loads or loads exceeding 16A, a contactor must be used. The timer controls the contactor coil, which in turn switches the main load circuit. Connect the timer's output (NO terminal 3) to one side of the contactor coil, and the other side of the coil to Neutral (N). The main power for the load passes through the contactor's power contacts.
Figure 5: Wiring for TM928SAKL (16A) with Contactor
4.2.3 TM928SBKL (30A Model) Direct Load Wiring
For loads up to 30A, the TM928SBKL model can directly control the device. Connect the Line (L) and Neutral (N) to terminals 1 and 2 respectively for power supply. The load is connected between terminal 3 (NO - Normally Open) and the Neutral (N) line. Terminal 4 (NC - Normally Closed) is not used in this configuration.
Figure 6: Wiring for TM928SBKL (30A) Direct Load
4.2.4 TM928SBKL (30A Model) with Contactor
For inductive loads or loads exceeding 30A, a contactor must be used. The timer controls the contactor coil, which in turn switches the main load circuit. Connect the timer's output (NO terminal 3) to one side of the contactor coil, and the other side of the coil to Neutral (N). The main power for the load passes through the contactor's power contacts.
Figure 7: Wiring for TM928SBKL (30A) with Contactor
5. Operation
The timer switch has a clear LCD display and several buttons for configuration: MENU, Up Arrow, Down Arrow, OK, and Res (Reset).
Figure 8: Timer Display and Control Buttons
5.1 Unlocking the Device
If the display shows "LOCK ON", the device is locked to prevent accidental changes. To unlock:
- Press and hold the MENU button for approximately 3 seconds.
- The "LOCK ON" indicator will disappear, and the device will be ready for programming.
Video 1: Demonstrates unlocking the device, setting current time, and cycling through ON/OFF programs.
5.2 Setting Current Time
After unlocking, you can set the current time:
- Press the OK button to enter time setting mode.
- Use the Up Arrow and Down Arrow buttons to adjust the hour, minute, and day of the week.
- Press OK again to confirm each setting and move to the next.
5.3 Programming ON/OFF Cycles
The timer supports up to 16 ON/OFF programs per day/week. To set a program:
- Press the MENU button repeatedly until you see "1 ON" (for the first ON program).
- Use the Up Arrow and Down Arrow buttons to set the desired time (hour, minute, second) and day(s) of the week for this ON event.
- Press MENU again to move to "1 OFF" (for the first OFF program).
- Set the desired time and day(s) for this OFF event.
- Repeat for up to 16 ON/OFF pairs.
- To exit programming mode, press the OK button.
5.4 Manual Override (ON/OFF/AUTO)
You can manually switch the timer's output state or set it to automatic mode:
- Press the MENU button and the Up Arrow button simultaneously to cycle through the working statuses: ON (always on), ON AUTO (currently on, will follow programs), OFF (always off), OFF AUTO (currently off, will follow programs).
- Select the desired mode. For programmed operation, ensure it is set to either "ON AUTO" or "OFF AUTO".
5.5 Resetting the Device
To clear all settings and return the timer to its factory default state:
- Locate the small Res (Reset) button.
- Use a pointed object (like a pen tip) to press the Res button. The display will reset.
6. Maintenance
6.1 Battery Information
- TM928SAKL (16A Model): This model includes a replaceable CR2032 battery. If the display becomes dim or the timer loses settings during a power outage, the battery may need replacement. To replace, carefully open the battery compartment on the back of the unit and insert a new CR2032 battery, ensuring correct polarity.
- TM928SBKL (30A Model): This model has a built-in, non-replaceable internal battery. It is designed for long-term use without battery maintenance. Do not attempt to open the unit to replace the battery.
Figure 9: TM928SAKL (16A) with Replaceable CR2032 Battery
Figure 10: TM928SBKL (30A) with Non-Replaceable Internal Battery
6.2 Cleaning
Wipe the exterior of the timer switch with a soft, dry cloth. Do not use abrasive cleaners or solvents.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Display is blank or dim | No power supply; Internal battery low (16A model) | Check power connections. For 16A model, replace CR2032 battery. |
| Timer does not switch ON/OFF as programmed | Incorrect program settings; Manual override active; "AUTO" mode not selected | Verify program times and days. Ensure operating mode is "ON AUTO" or "OFF AUTO". |
| Load does not turn ON/OFF | Incorrect wiring; Overload; Faulty load | Check wiring against diagrams. Ensure load current does not exceed timer rating. Test load separately. |
| Device is locked, cannot program | Lock function is active | Press and hold the MENU button for 3 seconds to unlock. |
| Time is incorrect after power outage | Internal battery is depleted (16A model) | For 16A model, replace CR2032 battery. For both models, ensure the timer is powered for a few hours to charge the internal battery. |
8. User Tips
- Ease of Use: Many users find this timer very easy to mount and program. Take your time to understand the programming steps, and you'll find it straightforward.
- Verify Settings: After programming, always double-check your ON/OFF times and selected days to ensure they match your intended schedule.
- Battery Check (16A Model): If you have the 16A model, consider having a spare CR2032 battery on hand, especially if the timer is in an area prone to power fluctuations.
9. Warranty and Support
For warranty information, technical support, or service inquiries, please refer to the documentation provided at the time of purchase or contact your vendor. Keep your purchase receipt as proof of purchase.
