Replacing the capacitor and triac on the "accelerator pedal" of a sewing machine

ID: 163357

Description: If the "accelerator pedal" on your sewing...

Steps:

1. Disconnect the powerplug!
2. Open the device. Compare with this wiki. You may have to look for the catches or the screws with which it is locked. On this model, the pedal is only engaged. Pay attention to the moving plate and the spring.
3. If the casing is closed with screws, make sure you keep them safe after removing them: you will need them again later!
4. Expose the circuit board so that you can reach the underside to desolder the components.
5. This is the triac. Desolder its three legs on the underside. These instructions tell you how to check it. Replace it if necessary.
6. Here are two capacitors. Read their capacitance. Desolder them and measure them with a suitable digital voltmeter. Replace them if necessary.
7. Look for the same type, usually MKP, the same dimensions, the same voltage and the class, usually X2.
8. Fuse. Measure its continuity and replace if necessary. Remember that a blown fuse usually has a reason.

9. Position the new components (capacitor and triac) in the appropriate places on the circuit board and solder them in carefully.
10. Verify the soldering points with a multimeter to ensure that all connections are correct and stable.
11. Reassemble the accelerator pedal housing and reinstall the screws or catches.