ESP8266 Community Forum

- Mon Mar 28, 2022 6:09 am #94105 I've also used lots of those modules (mainly the 3.3V version to power ESP-12F directly) and not had any failures .
Being super cautious I use just a simple wire fuse (pico) in-line with the live feed to guard against any catastrophic failure. I use a slow blow (e.g. 1A) . Fast blow can fuse on the turn-on surge current.

These fuses look like small resistors and therefore take up no significant extra space. One can use a sleeve or heatshrink if included in-line.

- Mon Mar 28, 2022 6:23 am #94106 There are also "Poly switches" resettable fuses, through hole and surface mount. The surface mount are quite large. I have just used one in a project.

- Mon Mar 28, 2022 6:30 am #94107

Being super cautious I use just a simple wire fuse (pico) in-line with the live feed to guard against any catastrophic failure. I use a slow blow (e.g. 1A) . Fast blow can fuse on the turn-on surge current.

Thank you for this... didn't know such a thing existed. I used automotive style and they are rather cumbersome!

Question - The running circuit, on the AC current side should be less than 0.01 amps. The surge is enough to blow a 1A fuse???

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- Mon Mar 28, 2022 4:02 pm #94113 I originally used a 250mA fast blow and these blew on the surge. The surge current can be quite high as switch mode supplies like this typically charge a reservoir capacitor through a bridge rectifier and if switched on when the AC is at a peak the surge could be quite high.

I suspect a slow blow of 250mA would be fine. I had a mix of 500mA and 1A slow blow which were both OK. The fuse is there primarily for a catastrophic failure and so I am not so bothered about using resettable ones. You also need fuses which are rated to sustain the break at the line voltage (e.g. 240V AC). That is available for the pico but limits the choice for resettable.