what is the pressuer of the nitrogen blader inside the  accmulator of  the 61 m schwing pump?

100 bar nitrogen pressure, 200 bar hydraulic system pressure; be sure to check and adjust both settings, as they work together 

yep..100 Bar Pre-Charge. Dump the accumulator when activated, and watch where the gauge drops to. Should drop quickly, then steadily drop down to 100PSi then drop to 0.. if it's a little below that, its usually OK, but if its too low, or drops to 0 instantly its either blown, or needs re-charged (depending on dropping position)

The gauge on the pump is a good guideline but they can become inaccurate over time as they wear out. It's usually best to screw a gauge to the top of the accumulator before you go to fill it. Once you put a gauge on the accumulator itself, you know what your pump's gauge should read for 100bar pressure if it's wearing out. 

From my experience, i started watching the gauge when the system builds the pressure, instead of releasing the pressue. i have seen the pressure drop at  the gauge at 80bar, put the charge kit for the bladder on, just to find out That the pressure is good at 100bar. I have found this to be more accurate.  Just a thougt.