Is it possible to detect specific UVB wavelength ranges using just a UVM-30A UV sensor or similar
Obviously this sensor is sensistivy for UV-B and UV-A radiation (even more sensistive for UV-A than for UV-B).

Therefore: no you can not just use this sensor.
At least you need also a filter that blocks UV-A but passes UV-B (using a monochromator would be total overkill; as it requires not only a prism or grating but also some collimating elements like mirror or lense with elaborate setup)