Induction Heater Layout
Thought for 14 sec
A 5 A fuse can be used temporarily, but 4 A is safer and preferred for this ~3 A / 72 W design.
A 5 A fuse does not limit normal current to 5 A; depending on its time-current curve, it may carry substantially more than 5 A for seconds or minutes. That reduces protection for the perfboard wiring, chokes, MOSFETs, connectors, and supply.
If using the 5 A fuse:
- Use it only if the supply itself has a reliable 3 A current limit.
- Ensure the fuse is rated for at least 32 VDC; an automotive blade fuse is suitable for 24 V DC.
- Use 14–16 AWG input wiring and heavy copper buses.
- Do not increase the supply current above 3 A merely because the fuse is 5 A.
- Fit the fuse in the +24 V input, close to the connector.
- Replace it with a 4 A time-delay fuse when available.
For initial tests, set the bench supply to 0.5–1 A, verify stable oscillation, and then increase gradually toward 3 A. If your power supply cannot current-limit, I would not recommend powering this build with the 5 A fuse alone.
E102 20Kv is this ceramic cap to large to substitute C3???
Thought for 14 sec
No.
102 means 1,000 pF = 1 nF = 0.001 µF. C3 requires 100 nF = 0.1 µF, normally marked 104.Therefore, the E102 is 100× too small in capacitance. Its 20 kV rating is harmless electrically but unnecessary, and the part may be physically large with long leads—poor for high-frequency bypassing.
For C3, look for:
- Marking: 104
- Capacitance: 100 nF / 0.1 µF
- Voltage: 50 V minimum; 100 V preferred
- Type: ceramic disc or small film
- Mount with the leads as short as possible
The required part may say
104, 104K, 104Z, 0.1uF, or 100nF.
