| ??? 06/12/07 14:47 Modified: 06/12/07 15:17 Read: times |
#140596 - Only, if you buy the cheapest ones... Responding to: ???'s previous message |
Jan said:
They have several pF of capacitive coupling between "primary" and "secondary", and the isolation voltage is not THAT high, either. Only, if you buy the cheapest ones... Nevertheless, you must forget the idea that an opto isolator is entirely isolating your circuit from the rest of the world. That's idiotic. You can hamper a bit the flow of low frequency currents, but at higher frequencies the isolation melts. The best idea is to use an opto isolator in combination with a common mode choke. By this you can tremendously enhance the high frequency "isolation". Also, in certain applications it can be a good idea to protect the barrier of an opto by a suited MOV. Kai |
| Topic | Author | Date |
| Under/Over Voltage Protection | 01/01/70 00:00 | |
| How Big a Motor | 01/01/70 00:00 | |
| Transients | 01/01/70 00:00 | |
| never thought of that, but worth emphasizing | 01/01/70 00:00 | |
| Crikey! | 01/01/70 00:00 | |
| carve this into stone | 01/01/70 00:00 | |
| Only, if you buy the cheapest ones... | 01/01/70 00:00 | |
| i've heard | 01/01/70 00:00 | |
| voltage dips | 01/01/70 00:00 | |
| I doubt it | 01/01/70 00:00 | |
| power dips and spikes | 01/01/70 00:00 | |
| Dippy | 01/01/70 00:00 | |
| How long lasts the mains dip? | 01/01/70 00:00 | |
| mains dip | 01/01/70 00:00 | |
Sprinkle as many caps as possible... | 01/01/70 00:00 |