Timeline for Filter for Spectrum Analyzer
Current License: CC BY-SA 3.0
13 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jan 24, 2018 at 21:42 | vote | accept | JC- | ||
| Nov 27, 2017 at 18:41 | comment | added | Bimpelrekkie | Note how quite some electronics are involved. If that probe is too expensive and the optical solution too complex (since an additional circuit is needed) then you could also make a voltage divider from one of the phases to ground. If the resistor between phase and output is at least 1 M ohm then the shock cannot be dangerous. | |
| Nov 27, 2017 at 17:52 | comment | added | Bimpelrekkie | From the Belkin link I see that they are analyzing up to 133 kHz which should be suitable for an optical solution, something like the circuit used here: electronics.stackexchange.com/questions/150588/… That still needs some circuit at the phototransistor side though. An easier solution is a ready made probe designed for mains probing with an oscilloscope: uk.rs-online.com/web/p/oscilloscope-probes/7296677 A teardown of which is here: eevblog.com/forum/testgear/… | |
| Nov 27, 2017 at 15:20 | comment | added | JC- | I understand that you are a top ten user and I am a first time poster and I appreciate your insight on shock protection. But now that you see what I mean by "2 phase" what changes do you suggest me to make on the above linked diagram of the power line interface to make it compatible with my network? | |
| Nov 27, 2017 at 10:02 | comment | added | Bimpelrekkie | Oh, OK, I did not expect that, thanks for sharing. | |
| Nov 27, 2017 at 8:43 | comment | added | JC- | No, fase + nul + aard is what I consider standard and I called 'other parts of the world'. Belgium and Norway has fase + fase + aard as described here: In sommige oude driefasennetten in België is de spanning van de fasen ten opzichte van de nulleiding 130 V. Om 230 V te krijgen worden fasedraad en nuldraad op twee fasen aangesloten. In Nederland bestaan dit soort netten niet meer. | |
| Nov 27, 2017 at 6:38 | comment | added | Bimpelrekkie | No, capacitors do not isolate from the mains. If you'd hold one connection of a 100nF 900V capacitor and stick the other connection in a mains socket, you would still get a shock. Mains is AC and capacitors do not block AC. In The Netherlands we do have "fase" (phase) and "nul" (neutral) but the neutral is not connected to a (local) ground as in some countries. It is probably the same as in Belgium. | |
| Nov 26, 2017 at 22:32 | comment | added | JC- | Thank you for the comment. I understand your concern but an isolation transformer would defy the purpose of this experiment. I assumed those 900V polypropylene capacitors serve to isolate from the mains. Do you have the same Neutral-less network in the Netherlands? | |
| Nov 25, 2017 at 17:05 | answer | added | delanymichael | timeline score: 2 | |
| Nov 25, 2017 at 16:17 | comment | added | Bimpelrekkie | Realistically you would want proper mains isolation, that could be a transformer, this could attenuate some of the high frequencies you're interested in. Another solution could be an opto-isolator. The referenced article's schematic doesn't show any mains isolation. But then, the authors have Indian names and I've often seen that they have a lighter attitude regarding mains safety compared to engineers in the western societies. But, don't skimp on mains isolation. When in doubt: get an expert's opinion! | |
| Nov 25, 2017 at 16:11 | comment | added | Bimpelrekkie | Even if there was a neutral connection, you still should not connect anything that isn't fully isolated. The name "neutral" suggests that there's no voltage present (with respect to ground). In practice there very often is a voltage present. It might not directly fry any measurement equipment but it can trip the GFCI (good) or shock the user (bad). | |
| Nov 25, 2017 at 15:46 | review | First posts | |||
| Nov 25, 2017 at 16:21 | |||||
| Nov 25, 2017 at 15:44 | history | asked | JC- | CC BY-SA 3.0 |