Deep Cycle Battery Charger - Leave Connected?

[Macavity]

Question roughly implied in the title. But something I never really know...

I'm very happy with a Deep Cycle battery and *dedicated* charger.

I have voltage & current (via shunt) monitoring at the battery too.

In a state of modest discharge, I connect the charger to the battery,

plug charger into the mains and away we go. A small LCD displays

percentage charge. When 100% it stop charging and displays "float".

As the voltage falls, the charger kicks in automatically to top up....

Still with me? lol. My question! 

If I leave the charger connected to the battery and switch off the MAINS

input , or remove the mains cable, will it load / discharge the battery.

I usually pull out a low voltage plug / socket between charger / battery!

The charger boasts that it can be "left connected"... But to what?

I sense the voltage decreases slightly (slowly) in this state. Just a bit

unclear about how exactly "float" chargers are designed to work!

[Freff]

My understanding of my charger is it can be left connected to the mains output switched on. The charger will monitor the battery condition and trickle charge when required.

A battery will discharge if connected to the mains (no power) or not, and at a rate dependent on the ambient conditions and the age/state of the battery. HTH