| ??? 01/18/05 02:07 Modified: 01/18/05 02:19 Read: times |
#85143 - Some disadvantages Responding to: ???'s previous message |
Prahlad said:
Kai, also please let me know is my method a correct one for measuring inductance. described here http://www.8052.com/forum/read.phtml?id=85070 The formula seems to be wrong for me as you did assume Zc = wL + Rc at a certain step. Because there's a phase shift between current and voltage at the inductance 'L', 'Zc' must be the geometrical sum of 'wl' and 'Rc', which yields Zc = SQRT ((wL)^2 + Rc^2). Your methode with the 50Hz signal has two disadvantages: 1. If you use mains voltage for the 50Hz signal, then you must expect something relevantly differing from a true sine. This is unwanted, because impedance of inductance 'L' rises with 'w', means the harmonics can play an unsane role in your measurement. 2. 50Hz is a bit too low for this measurement, because 'wL' is rather low at this frequency. Using a higher frequency would be much better suited. I dont have a signal generator will it be fine if I use some PC software for generating sine waves through my sound card. Sine generator can very easily be built by the help of some OPamps, small signal diodes and a N-channel FET. Extremely cheap and helpful. Kai |
| Topic | Author | Date |
| Source Impedance | 01/01/70 00:00 | |
| Re | 01/01/70 00:00 | |
| Impedance measurement | 01/01/70 00:00 | |
| Being more concrete | 01/01/70 00:00 | |
| What about my Rogowski Coils. | 01/01/70 00:00 | |
| Already answered in detail! | 01/01/70 00:00 | |
| Re: ' Detailed Answer' | 01/01/70 00:00 | |
| Bridge | 01/01/70 00:00 | |
| What Bridge, | 01/01/70 00:00 | |
| bridge | 01/01/70 00:00 | |
| and ... | 01/01/70 00:00 | |
| Using an OPamp | 01/01/70 00:00 | |
| Using OpAmp | 01/01/70 00:00 | |
| Some disadvantages | 01/01/70 00:00 | |
| Correct formula | 01/01/70 00:00 | |
| Thanks Kai, | 01/01/70 00:00 | |
| LCR meters quite common | 01/01/70 00:00 | |
Re: LCR Meter. | 01/01/70 00:00 | |
| Resonant coupling... | 01/01/70 00:00 | |
| Sorry! | 01/01/70 00:00 | |
| Go with the rule of Thumb | 01/01/70 00:00 | |
| No more than about 10kOhm | 01/01/70 00:00 | |
| Line drops | 01/01/70 00:00 | |
| Thicker cable | 01/01/70 00:00 | |
| Freq domain analysis | 01/01/70 00:00 | |
| re: Source Impedance and driver types | 01/01/70 00:00 | |
| universal solution | 01/01/70 00:00 | |
| Thanks .... | 01/01/70 00:00 |