1. OVERVIEW
English
© Siemens plc 1999
G85139-H1751-U529-D1
11
4/8/99
1.3.2 The use of residual-current protective devices
Drive inverters can be operated with residual-current protective devices under the following conditions:
·
1-phase:
Residual-current protective devices with 300mA (type A) are permissible
·
3-phase:
Universal residual-current protective device with 300mA (type B) must be used.
·
Only one drive inverter may be connected to a residual-current protective device.
·
The neutral conductor of the line supply must be grounded.
·
The motor cables may not be longer than 50m when shielded or 100m when non-shielded
·
The pulse frequency (P076) may not exceed max. 4kHz
1.3.3 Installation after a Period of Storage
It is necessary to reform the capacitors in the inverter if the unit has been stored for a prolonged period:
·
Period of storage 1 year old or less:
No reforming is required.
·
1 - 2 years old:
Apply power to the inverter one hour before giving the run command (preparation time 1 hour).
·
2 - 3 years old:
Use a variable AC supply. Apply 25% of input voltage for 30 minutes. Increase volts to 50% for a further
30 minutes. Increase volts to 75% for further 30 minutes. Increase volts to 100% for a further 30 minutes.
Now ready for run signal (preparation time 2 hours).
·
3 years and over:
As with 2 - 3 years, but the steps should be 2 hours (preparation time 8 hours).
1.3.4 Operation with Long Cables
Motor cable lengths vary depending on type of cable, power rating and voltage rating - and in some cases can be as long as 200m
without the need for additional chokes. Refer to DA64 catalogue for further details.
In any case, all inverters will operate at full specification with cable lengths up to 25m for screened cable or 50m for unscreened
cables.
