I bought about year ago NX3224F024_011R for battery project and it worked well.
From Nextion documenation site:
32 lowpower Low Power Discovery Series. Low Power 0.25mA deep sleep
A few days ago I bought 2 same displays and lowpower=1 only a little decrease mA usage.
With ‘lowpower=0’ is about 17mA and with ‘lowpower=1’ 11mA.
The first display with lowpower=1 shows on measure 1mA (it is acceptable).
The new two displays models are same, firmware same, program same, everything is the same, the only difference is that the first was produced some time ago.
I perform a test with above command and sleep=1 and results are same.
FIRST (WORKS GOOD):
Connected! Com:COM6,baudrate:9600,Model:NX3224F024_011R(RTP),firmware Ver:S72,Device serial number:0B663401CC158C3D,CPUID:61744,Flash Size:4194304(4MB)address:0
Forced upload baudrate:115200 Start uploading
Download finished! Total time: 0 Hours 0 Minutes 33 Seconds
SECOND (WORKS BAD):
Connected! Com:COM6,baudrate:9600,Model:NX3224F024_011R(RTP),firmware Ver:S72,Device serial number:228D340142FC0455,CPUID:61744,Flash Size:4194304(4MB)address:0
Forced upload baudrate:115200 Start uploading
Download finished! Total time: 0 Hours 0 Minutes 33 Seconds
THIRD (WORKS BAD):
Connected! Com:COM6,baudrate:9600,Model:NX3224F024_011R(RTP),firmware Ver:S72,Device serial number:228D3401C678F650,CPUID:61744,Flash Size:4194304(4MB)address:0
Forced upload baudrate:115200 Start uploading
Download finished! Total time: 0 Hours 0 Minutes 33 Seconds
Look at photo: