Hello Bernd,
up to now there is no "ASCII" data type in the EX Sensor protocol.
Of course you could misuse the "unit" data field of the sensor channel to display up to 4 chars (DS / DC-16) or 3 chars (JB Profi), but the problem with this workaround is the update frequency of this data type on the Jetibox side... It seems that this data field is only read once when the sensor is recognized ("learned in"), or at least it is updated with a very low frequency. Too bad - unusable for your purpose... Test setup with a sensor / data field named "Turbine: Status" see attached JPG.
I also had the same problem with a KTW controller project (which is a Jeti MUV sensor in parallel), at the end I just used the numeric 6-bit data type to send the KTW status there.
=> Jeti developers:
If you read this, please think about a "dedicated ASCII" Duplex EX data type with at least 8 chars, e.g. formatted like the sensor name / unit field which is already in use. This would make all kinds of status info much easier. Thanks!