As others have suggested,  its dependant  on the  model of  charger you  have in  your caravan. The reason is the types of chargers fitted to  caravans have changed over the years,  and older ones do not  have the multistage charging  of  more recent  versions.
Without  detailed knowledge of the  type of charger in  your caravan, it  might  be unwise to  fit  the new battery and leave it charging 24/7.
Also it is potentially a waste of power,  when if its simply  to  maintain the charge in the battery,  just  a few hours each  month  should be more than  sufficient.  Perhaps consider getting  a 7 day time  switch,  and set  it  run for  an hour every  week ,  you could do it  in the  Economy  seven period to  keep  costs down. 
If 24/7 charging  is essential  for you,  then I  suggest  consider getting  a separate dedicated multistage  charger to  do  it  for you. There are some premium (comparatively  expensive) brands (e.g. Ctek or  Noco)  which are excellent and not only  look after the battery very well, but  can also  be used to bring an older or over discharged battery back  to  some life.  
However the likes of Aldi  and Lidl usually once or twice a year have some lower cost but almost as effective multi- stage battery  chargers. One note of  caution I know the Ctek  models I have used have all resumed the  set  charging  cycle if there has been a power cut,  but the supermarket  models usually  need to  manually reset after a power cut.