Dissimilar Pitch Neutral Limiter

GENLINK DPNL is a multiple winding reactor that, when installed in the common neutral of paralleled sources either between the dissimilar generators or the generator and the utility supply, can greatly reduce the neutral circulating currents that result from the instantaneous voltage differences. These neutral circulating currents, which are predominantly triple frequency, have the potential to cause a considerable amount of damage with respect to overheating generators and causing false-protection trips.

Voltage differences in paralleled generators made by different manufacturers or differences in standard pitch design configurations in generators made by the same manufacturer can result in heavy neutral circulating currents. Additionally, alternative energy sources such as solar and wind power that generate AC power can introduce heavy circulating currents in 4-wire parallel applications. When applied, GENLINK will impede the flow of circulating currents while adding only minimal impedance to the fault current path.

GENLINK DPNL can be used in both 3-wire and 4-wire systems. For 4-wire applications where there is return neutral current from 1-Ph loads, the DPNL must be sized for this current as well as the circulating current. For 3-wire applications where there is no return neutral current from 1-Ph loads, a smaller size DPNL can be used. Grounding of the neutral must be done at only one location, which is recommended to be the distribution switchboard.

Features

• Inserts >40% impedance in neutral current circulating path
• Reduces neutral circulating current by >75%
• Adds <1% saturated impedance to 1-Ph fault path
• No impedance to 3-Ph fault path
• Use in 3-wire or 4-wire applications or any parallel source application with a common neutral and dissimilar voltage waveforms
• Eliminates generator overheating and false protection trips caused by triple frequency circulating currents
• Easy to install
• Reliable and proven performance