No problem IFix - we all have our bad days. Apology accepted; I will remove my reference to it
Chris; yes, that is exactly what I am refering to; The accumulator smooths pressure fluctuations (and covers short term pressure drops as Ifix says). If an accumulator had lost its nitrogen charge, I thought any pressure fluctuations in the HYD system might trigger the PTU just for a moment, each time, causing the 'barking dog syndrome'.
Not being an aircraft engineer, I don't know what the maintenance procedures are, but no we don't have any cockpit indication of accumulator pressure, so this might go undetected until the next hangar visit?