Siemens A1 ユーザーズマニュアル
Selecting a Drive
International English
10
MICROMASTER Applications Handbook
Supplies at the end of long power lines in remote areas can rise excessively in the
evening and weekends when large loads are no longer present.
evening and weekends when large loads are no longer present.
Industries with locally controlled and generated supplies can have poor regulation
and control.
and control.
Power systems in certain parts of the world may not meet expected tolerances.
In all installations, check that the supply will remain within the tolerances stated
above. Operation outside of the stated supply levels will probably cause damage.
above. Operation outside of the stated supply levels will probably cause damage.
3.2.2 Supply
Disturbance
Many supplies are well controlled and remain in tolerance, but are affected by local
disturbances. These can cause faulty operation and damage to inverters. In
particular, check for:
disturbances. These can cause faulty operation and damage to inverters. In
particular, check for:
· Power Factor Correction equipment. Unsuppressed switching of capacitor
banks can produce very large voltage transients and is a common cause of
inverter damage.
inverter damage.
· High power welding equipment, especially resistance and RF welders.
· Other drives (in particular large, old DC drives), semiconductor heater
controllers etc.
Note.
Inverters are designed to absorb high levels of supply disturbance. Voltage spikes
up to 4 kV for instance. However, the above equipment can cause power supply
disturbances in excess of this. It will be necessary to suppress this interference -
preferably at source - or at least by the installation of an input choke in the inverter
supply. EMC filters do not suppress disturbances with this level of energy; over
voltage protection products such as metal oxide varistors should be considered.
Inverters are designed to absorb high levels of supply disturbance. Voltage spikes
up to 4 kV for instance. However, the above equipment can cause power supply
disturbances in excess of this. It will be necessary to suppress this interference -
preferably at source - or at least by the installation of an input choke in the inverter
supply. EMC filters do not suppress disturbances with this level of energy; over
voltage protection products such as metal oxide varistors should be considered.
Damage can also be caused by local supply faults and the effects of electrical
storms. In areas where these are expected, similar precautions are recommended.
storms. In areas where these are expected, similar precautions are recommended.
Figure 3-1
Sources of Supply Disturbance
MICROMASTER
Motor
Power Factor
Correction
Equipment
Correction
Equipment
Welders
RF Heaters etc.
Large Drives and
Power Electronic
Systems
Power Electronic
Systems
Lightning, Power
System Faults
System Faults
Add input inductor and
Over Voltage Protection
Equipment here.
Over Voltage Protection
Equipment here.