In low voltage installations, when a capacitor is connected, a higher degree of resonant phenomenon is produced. Apart from the nominal current, an overcurrent of amplitude greater than 180xIn is produced. The resulting current peaks, caused by the connection of the capacitors, depend on the following factors:
• Inductances in the network.
• Power transformers and short-circuit voltages.
• Fixed or automatic power factor correction systems.
• Presence of harmonics in the network.
Current surge of such a large magnitude is undesirable and could very well damage standard contactors.
For this reason, the use of specific contactors for capacitors is recommended. The MOC class AC-6b model from RTR Energía guarantees correct operation for this application
Electromagnetic contactors for capacitor applications are designed to meet special operating requirements.
These contactors incorporate a front block and six limiting resistors to dampen the current peak in the connection of the capacitors.