| ??? 09/11/07 11:56 Read: times Msg Score: +1 +1 Good Answer/Helpful |
#144367 - NON-linear ??? Responding to: ???'s previous message |
Jprao said: NON- linear ??? If thats the case why do you accept it ?
I am using imported resistor divider (1M/1000M). It is giving entirely non-linear readings. The voltage coefficient is good.
My DPM is 2V DPM. I can replace it to 20V DPM also. But my ADC is 12-bit with VREF 2.5V. with this ADC, I can count only 4096. This resolution also may not sufficient I feel for this purpose. We can't suggest unless you specify. What IS your acceptable resolution. Is your measurement means floating or is it tied to ground. Add more divider chain to get the input range you want. If we assume that eventually you are scaled so that 2.5 volts = 6kv on your input. 4095 counts= 6kV and you have a resolution of 1.5 Volts. Rescale the system so that 0 digits =0 counts, not 380 and you have 1.34 volts per digit. Thats the best you can do. Its not so much better than 1.5 volts that its worth worrying about. Steve |
| Topic | Author | Date |
| High Voltage measurement | 01/01/70 00:00 | |
| reply | 01/01/70 00:00 | |
| Proper reading? | 01/01/70 00:00 | |
| non linear | 01/01/70 00:00 | |
| Resistor divider rating | 01/01/70 00:00 | |
| NON-linear ??? | 01/01/70 00:00 | |
| what is 'across' the 1M | 01/01/70 00:00 | |
| Does it matter | 01/01/70 00:00 | |
| e.g. A \'protection diode\' may leak a bit | 01/01/70 00:00 | |
| Parasitic ? | 01/01/70 00:00 | |
| DPM are normally very highohmic ... | 01/01/70 00:00 | |
| the problems | 01/01/70 00:00 | |
| A good idea, indeed! | 01/01/70 00:00 | |
| DPM input | 01/01/70 00:00 | |
| Thanks to all | 01/01/70 00:00 | |
| That's all very well | 01/01/70 00:00 | |
| Yes, Jprao, please answer our questions! | 01/01/70 00:00 | |
| DIffierent Divider Perhaps | 01/01/70 00:00 | |
| DPM? | 01/01/70 00:00 | |
| DPM is a widely used term... | 01/01/70 00:00 | |
| many DPMs use ICL7106 | 01/01/70 00:00 | |
Yes, evolves into a heart-stopping thread... | 01/01/70 00:00 |