| ??? 04/07/05 21:01 Read: times |
#91208 - It's a loop and a flop Responding to: ???'s previous message |
Anyhow, it is simple to try, why don't you. Test conditions: Machine and control sitting on kitchen counter type bench, separated by about 2 feet. Piezo zapper grounded to outside of control cabinet. Test 1) Both end of cable have shield bonded to connector housing. Control end of shield connected to control cabinet. Result 1: 50 piezo zaps to machine end of connector housing caused nothing. 40 other zaps to control end of cable and various other spots. The last zap on the PCB mounting screw nearest the crystal for the uC caused a reset. Test 2) Remove shield connection at machine end. Result 2: One piezo zap to machine end of connector housing caused uC to hang. Test 3) Connect machine to safety ground of control via 18 ga wire, external to shielded cable. Shield connection still removed from machine end. Result 3: One piezo zap to machine end of connector housing caused uC to hang. Test 4) Remove shield connection at control end only, no safety ground connection from machine to control. Result 4: One piezo zap to machine end of connector housing caused uC to hang. Test 5) Add safety ground connection from machine to control to test 4. Result 5: Same results as 2, 3, and 4 Anybody need a job? It's medium pay and requires a hat with programmable display :( Jon |
| Topic | Author | Date |
| What do you think could happen if... | 01/01/70 00:00 | |
| The 10k from RST to GND | 01/01/70 00:00 | |
| Random resets.. | 01/01/70 00:00 | |
| Dogma. | 01/01/70 00:00 | |
| Oh yea ? | 01/01/70 00:00 | |
| Hmm | 01/01/70 00:00 | |
| brown outs | 01/01/70 00:00 | |
| Obscure | 01/01/70 00:00 | |
| RC Reset circuits. | 01/01/70 00:00 | |
| Something more to it ... | 01/01/70 00:00 | |
| ad wars between Maxim and Microchip | 01/01/70 00:00 | |
| Cutting teeth... | 01/01/70 00:00 | |
| recommend brown out detectors | 01/01/70 00:00 | |
| Which depends on for what.. | 01/01/70 00:00 | |
| built-in reset | 01/01/70 00:00 | |
| Re: Built in brown out? | 01/01/70 00:00 | |
| Better than I did.... | 01/01/70 00:00 | |
| Thanks, Michael. | 01/01/70 00:00 | |
| Why | 01/01/70 00:00 | |
| Other stuff ? | 01/01/70 00:00 | |
| many reasons | 01/01/70 00:00 | |
| Thats not correct. | 01/01/70 00:00 | |
| speak with forked tongue | 01/01/70 00:00 | |
| I agree | 01/01/70 00:00 | |
| re: dogma | 01/01/70 00:00 | |
| ESD events and EMI | 01/01/70 00:00 | |
| Re: Random resets. | 01/01/70 00:00 | |
| Lets not reject the obvious! | 01/01/70 00:00 | |
| no R | 01/01/70 00:00 | |
| RC-circuits are bullshit!! | 01/01/70 00:00 | |
| RC-circuits are bullshit!! | 01/01/70 00:00 | |
| Reset Capacitor | 01/01/70 00:00 | |
| You missed the question! | 01/01/70 00:00 | |
| Why guessing? | 01/01/70 00:00 | |
| RE:Why Guessing | 01/01/70 00:00 | |
| Timing | 01/01/70 00:00 | |
| Update | 01/01/70 00:00 | |
| not necessarily the reset | 01/01/70 00:00 | |
| Other derivatives | 01/01/70 00:00 | |
| if no cap | 01/01/70 00:00 | |
| No Cap | 01/01/70 00:00 | |
| not just a cap, but the right cap | 01/01/70 00:00 | |
| Which cap? | 01/01/70 00:00 | |
| depends | 01/01/70 00:00 | |
| Yes Cap | 01/01/70 00:00 | |
| directly | 01/01/70 00:00 | |
| RE:Directly | 01/01/70 00:00 | |
| yes | 01/01/70 00:00 | |
| Absolutely ! | 01/01/70 00:00 | |
| Update - ESD Problem? | 01/01/70 00:00 | |
| some ways | 01/01/70 00:00 | |
| some ways - more detail please | 01/01/70 00:00 | |
| details | 01/01/70 00:00 | |
| Car induction coil | 01/01/70 00:00 | |
| ESD Problem | 01/01/70 00:00 | |
| Physical Separation | 01/01/70 00:00 | |
| Few Ideas | 01/01/70 00:00 | |
| Re: Few Ideas | 01/01/70 00:00 | |
| Check your external ground | 01/01/70 00:00 | |
| Ya. | 01/01/70 00:00 | |
| now that you are willing | 01/01/70 00:00 | |
| RE:Now that you are willing | 01/01/70 00:00 | |
| alot easier when you know what your look | 01/01/70 00:00 | |
| Not as bad as initially thought. | 01/01/70 00:00 | |
| ground loop | 01/01/70 00:00 | |
| RE: Ground Loop | 01/01/70 00:00 | |
| sound | 01/01/70 00:00 | |
| RE: Ground Loop | 01/01/70 00:00 | |
| It is a loop AND | 01/01/70 00:00 | |
| It's a loop and a flop | 01/01/70 00:00 | |
| no shield can help you there | 01/01/70 00:00 | |
| Kind of machine | 01/01/70 00:00 | |
| so your testbench setup should be OK | 01/01/70 00:00 | |
| Failures | 01/01/70 00:00 | |
| in that case | 01/01/70 00:00 | |
| Materials | 01/01/70 00:00 | |
| could still be ground | 01/01/70 00:00 | |
| Noise resistance | 01/01/70 00:00 | |
| you will not find that | 01/01/70 00:00 | |
| What can be found? | 01/01/70 00:00 | |
| tough these days | 01/01/70 00:00 | |
| Glue ? | 01/01/70 00:00 | |
| No Glue | 01/01/70 00:00 | |
| lesse some pictures. | 01/01/70 00:00 | |
| LOL | 01/01/70 00:00 | |
| Nope | 01/01/70 00:00 | |
| Let the fun begin! | 01/01/70 00:00 | |
| Confession | 01/01/70 00:00 | |
| Confession | 01/01/70 00:00 | |
| Ah. | 01/01/70 00:00 | |
| Not that bad | 01/01/70 00:00 | |
| HAr to see but | 01/01/70 00:00 | |
| Wiring & Filter | 01/01/70 00:00 | |
| Maybe a little better pictures here | 01/01/70 00:00 | |
| nice | 01/01/70 00:00 | |
| Oops - try again | 01/01/70 00:00 | |
| Uh Oh | 01/01/70 00:00 | |
| Yep | 01/01/70 00:00 | |
| Don't ground both ends of shield | 01/01/70 00:00 | |
| bonding | 01/01/70 00:00 | |
| RE: Bonding | 01/01/70 00:00 | |
| Useless.... | 01/01/70 00:00 | |
| Better Pix yet? | 01/01/70 00:00 | |
| Re: Better Pics Yet? | 01/01/70 00:00 | |
| DETAILS... | 01/01/70 00:00 | |
| Nothing hiding here! | 01/01/70 00:00 | |
| !!!!! | 01/01/70 00:00 | |
| I don't think so. | 01/01/70 00:00 | |
| !! | 01/01/70 00:00 | |
| Grounding. | 01/01/70 00:00 | |
| Grounding | 01/01/70 00:00 | |
| Prahlads points | 01/01/70 00:00 | |
| Clarification | 01/01/70 00:00 | |
| Clarification | 01/01/70 00:00 | |
| Update | 01/01/70 00:00 | |
| au contraire | 01/01/70 00:00 | |
| The answer may be on the horizon | 01/01/70 00:00 | |
| not the voltage, but the change | 01/01/70 00:00 | |
| Have a look see | 01/01/70 00:00 | |
| I do not know how good | 01/01/70 00:00 | |
| 7805 Starving | 01/01/70 00:00 | |
| it will go HOT | 01/01/70 00:00 | |
| Heatsink | 01/01/70 00:00 | |
or it's possible | 01/01/70 00:00 |