The wmr200.py should not report h'ff as a value out of range as there is no value from the UV-sensor as there is no sensor installed. Alternative report is record out of order, sensor lost or sensor not installed.
Debug and archive log info: Sep 27 06:00:35 RPi-3Bp-Arelien weewx[16407] DEBUG weewx.drivers.wmr200: UV index:255 Sep 27 06:00:36 RPi-3Bp-Arelien weewx[16407] WARNING weewx.qc: 2020-09-27 06:00:08 CEST (1601179208) Archive value 'UV' 255 outside limits (0.0, 6.0) Raw data from console: Sep 27 06:00:35 RPi-3Bp-Arelien weewx[16407] DEBUG weewx.drivers.wmr200: Packet raw:d2 70 07 05 1b 09 14 00 00 00 00 19 00 bb 41 00 0c 01 01 07 06 0c 0f 60 01 86 01 ff cd 43 cd 33 0a 00 e8 00 19 14 00 00 00 00 40 1d 3c 00 00 04 e1 00 29 5a 00 00 00 00 40 30 14 80 00 00 e9 00 15 00 00 00 0f 02 5e 56 46 80 00 08 01 55 52 5a 80 00 01 33 00 46 00 00 00 00 00 40 0f 50 80 00 00 00 40 25 3c 00 00 07 c5 00 23 28 00 00 50 12 Information on the D2-data: https://www.bashewa.com/wmr200-protocol.php *D5 UV ----------------------------------------------------------------------------------------* Byte 27: (xI) Reports value of [#ff] in history [D2] records when out of order, not installed or sensor is lost. (x) byte(27:H) .. unknown / always [#0] .. maybe alarm or sensor absent? (I) byte(27:L) .. UVI 0-15 ... (0-2 low / 3-5 moderate / 6-7 high / 8-10 very high / 11+ extremely high) -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/weewx-user/20860b37-a03f-4566-aacc-d2b83f3c110co%40googlegroups.com.