en/ACS800-04/U4 Hardware Manuals - VAE ProSys sro

46Note 7: Calculating the rise time and the peak line-to-line voltageThe peak line-to-line voltage at the motor terminals generated by the drive as well as the voltage risetime depend on the cable length. The requirements for the motor insulation system given in the tableare “worst case” requirements covering installations with 30 metre and longer cables. The rise time canbe calculated as follows: t = 0.8 · Û LL /(du/dt). Read Û LL and du/dt from the diagrams below. Multiplythe values of the graph by the supply voltage (U N ).With resistor braking, the Û LL and du/dt values areapproximately 20 % higher.3.02.5Û LL /U N5.55.04.5du/dt------------(1/μs)U N2.04.01.51.00.5du/dt------------(1/μs)U N3.53.02.52.01.5Û LL /U N0.0100 200 3001.0100 200 300Cable length (m)Cable length (m)With du/dt filterWithout du/dt filterNote 8: Sine filters protect the motor insulation system. Therefore, du/dt filter can be replaced witha sine filter. The peak phase-to-phase voltage with the sine filter is approximately 1.5 × U N .Note 9: Common mode filter is available as a separate kit (one box including three rings for one cable).Permanent magnet synchronous motorSupply connectionOnly one permanent magnet motor can be connected to the inverter output.It is recommended to install a safety switch between the permanent magnetsynchronous motor and the drive output. The switch is needed to isolate the motorduring any maintenance work on the drive.Disconnecting device (means)Install a hand-operated input disconnecting device (disconnecting means) betweenthe AC power source and the drive. The disconnecting device must be of a type thatcan be locked to the open position for installation and maintenance work.Planning the electrical installation