Guru
Joined: 02/02/2017
Location: AustraliaPosts: 1459
| Posted: 04:12am 26 May 2021 |
The picoverter PCBs have arrived.
I built one and it works perfectly.
No errors on the PCB
Later I will upload a BOM and build and startup instructions.
The 12V AC feedback circuit draws 1.5mA at 10.3 V AC
with my feedback transformer.
the firmware:
pico_1.ino.zip
The PCB files have been posted earlier.
The firmware works properly, with the LV cutoff and restart and the two
over temp stop and fan controls. All good.
Even the LCD works. The serial data is sent at 10,000 baud, due to the
code that sends the data is within the 20kHz main interrupt loop.
I divide by 2 for the bit transmission so that means
10,000 baud and not 9,600 baud. The nano/LCD that is running my serial LCD code
works fine with this too fast data rate. There is some tolerance in baud speed
matching and so far no issues.
LCD looks like this:
A bare bones display, just the data we need and nothing else.
The two temperatures are in deg. C and the star means the fan is running.
Output voltage is not shown, I did not need it so I did not design it in.
The HS NTC is not connected so it shows zero.
The picoverter will be just as useful without an LCD.
The on-board LED shows if the inverter is running.
The LED on the Nano will blink fast when the inverter was stopped
due to over temp of either HS or toroid.
It will blink slow if it's stopped due to under voltage.
If it's OK, it wont blink at all.
I probably will not need the LCD myself but it's here anyway for those who want it.