METHOD FOR ACCELERATING INSULATION RESISTANCE MEASUREMENT IN AN UNGROUNDED POWER SYSTEM

The invention relates to methods for accelerating insulation resistance measurement for application in a method for determining insulation resistance according to a pulse measurement method in an unearthed power supply system (IT system). Following a specification (55) of a target charge state (r) of the network capacitances present in the unearthed power supply system, a target time point (Tt) is calculated at which the network capacitances will have reached the target charge state, from the target charge state and an effective tau value (tau_eff). Subsequently, a first waiting time (dTr) is calculated starting from the current time point (T3) as the difference between the target time point (Tt) and the current time point (T3). In a second variant, alternatively a target charging speed (kt) is specified (35), which reflects a sufficiently steady-state charge state of the capacitors that is valid for the insulation resistance measurement. The target charging speed (kt) corresponds to the first-order difference quotient (V`2) of the target charging voltage (Vt) and is thus linked with the target time point (Tt). With knowledge of the already determined and stored first-order difference quotient (V'2), a time difference is calculated as a second waiting time (dTv).