Now I found a little mor information:
A HVPl was about 6-10 km behind the front. They was able to look for 25 heavy injured, 60 middle heavy injured or 120 little injured soldiers. If it was able a HVPl was in a building but if not, the division was able to stay in tents. No soldier should stay for longer time at HVPl to be able to look for a lot of injureds if it was necessary.
A Feldlazarett was about 20 – 25 km behind the front. It should have been so far away from the front, that the artillerie was not able to reach the lazarett. This lazaretts had special docs, the possibilty for x-ray, a dentist and a good pharmacy.