using SDR trying to get weewx to record rain in DB

[wilco van hoboken]

I have now been able to set up my new ACCUR8 7 in1 sensor to send the data properly to weewx.

so far all the data is coming in properly and recording that the sensor transmits. 

temp, hum, total_rain, wind_averg, wind_gust, wind_dir, UV and radiation are all recording in the database. so far so good.

now I would like to record the the rain. (delta of total rain) I see that this is standard in sdr.py under

 DEFAULT_DELTAS = {

        'rain': 'rain_total',

        'strikes': 'strikes_total'}

but there is no rain as such transmitted to weewx. 

I have also tried adding to weewx.conf under SDR

    [[deltas]]

        rain = rain_total

but this does not create the rain data in the database.

what am I missing

thx Wilco