I imagine that these industrial meters are designed to measure the ambient light in a room or other space, testing different lighting in workspace -- I am sure that there are building or safety codes for the amount of light required in a workspace. If the dome is permanent, the meter can be used as an incident light meter, but probably not as a reflective light meter.
If 20,000 Lux is the upper limit it can test, then the meter may not be very good for photography. Looking at the back of my Luna Pro SBC, I see that 22,000 Lux at ASA50 would be about f16 at 1/15th Sec (EV 12...or f8 at 1/60th)...if that is any help at all...and if I am reading it right!
I just looked on line at some of the industrial light meters, and they have a range of 0 to 20,000 Lux. Some are measured in foot candles (2000 ft candles is about 22,000 Lux). Some measure from 0 to 50,000 Lux...and as the price goes up, some meter 0 to 400,000 Lux...which is pretty good (4+ stops higher than 20,000), still not as high as most photographic lightmeters.
You get what you pay for! There are some good online charts for determining exposure without a meter.