Guru
Joined: 11/02/2018
Location: AustraliaPosts: 2398
| Posted: 11:51pm 08 Jun 2024 |
The main filter cap is the problem for a square-wave inverter (often called modified sinewave if it has PWM voltage regulation). A vertical rise in voltage at every half-cycle produces a massive current spike as it tries to instantly charge the cap to 300Vpeak.
It can also happen with a sinewave inverter if the SMPS is switched on close to the AC peak.
It happens less now as newer devices often have some form of surge limiting as noted in Mick's post above.
Edited 2024-06-09 09:54 by phil99