Guru
Joined: 21/06/2018
Location: AustraliaPosts: 1156
| Posted: 08:14am 05 Jul 2022 |
Ok new code installed and the ramp up grunt is very much reduced along with the peak current (down from ~450mA to ~ 390mA), but there is another interesting side effect too, this code when settled - there is a gentle buzzing that climbs and falls in level a bit - it takes a while (30 to 60 seconds to fully settle) and the input current also climbs and falls slightly (talking less than 10mA in 371mA) in sync with the buzz.
It all settles after ~ 1minute at ~ 17.1W & 371mA. There is then just a faint gentle hum just like the mains.
With the original code, the grunt is as strong as ever, it does not wander but just slowly decreases and settles to ~ 374mA & 17.3W but there is always a gentle buzz on top of the hum that never goes away completely.
I am not complaining or asking for any further changes here, I am simply reporting what I observed. I swapped the nanos back and forth 3 times to check that is was not only repeatable but also predictable.
I used to work with another older engineer and he would sometimes utter the statement that something was of monumental inconsequence - this may well be one of those events...... I suspect that if I reprogrammed the two nanos with each others code maybe it might be slightly different again.
Peter there is something I would really like to try if you would indulge me further if you have the time and patience.
During ramp up when Vfb = setpoint then no bang bang & go straight to pid. The other less preferred trial is, ok retain bang bang, but only increment and decrement level changes in pairs, ie at 50 Hz so changes are balanced whilst bang bang is shuffling back and forth. Which ever is easiest.
Edited 2022-07-05 18:17 by wiseguy