LV Active Network Management

Distribution networks are facing unprecedented challenges. Increases in demand, distributed generation, use of electric vehicles and heat pumps all require a new methodology of network management and control. The Kelvatek Low Voltage active network management system provides the monitoring, communications and control functions to help utilities create an LV network for the future.

WEEZAP is an LV vacuum circuit breaker combined with advanced measurement and protection capability. The compact retrofit design allows WEEZAP to be fitted directly to existing LV panels in replacement of the fuse. It is not necessary to replace the LV board itself. Fitting is simple and fast with a minimum of training.

The VCB design allows the WEEZAP to close and open the circuit at the LV substation either locally or remotely. The WEEZAP can protect the network by opening the circuit breaker in overload and fault conditions. Configuration settings allow local automated re-closing; alternatively reclose control can be via the Network Management System (NMS).

Operational Schematic

WEEZAP Key features

  • Automatic meshing and reconfiguration of the network using embedded LV switches
  • Monitor power quality parameters at key points on the network
  • Communicate data to and receive control commands from the Network Management System (NMS)
  • Advanced protection and fault isolation and location capability
  • Add new levels of safety for the LV network
  • Easy to install, retrofit design


WEEZAP and LYNX measure voltage, current, power factor, real power, apparent power, reactive power, frequency, THD and individual harmonics including magnitude and phase up to the 25th. Data intervals can be configured to calculate the mean values over a range from 1 minute to 1 hour. 10ms minimums and maximums are also recorded over this period.

WEEZAP and LYNX can:

  • Detect over and under voltage conditions/confirm voltage within limits
  • Monitor currents for overload and assess duration and magnitude of overloads
  • Check Harmonic Levels on the network
  • Use power flow information at NMS level to make network configuration decisions
  • Capture high speed data to diagnose network problems, including incipient fault detection and location


The GATEWAY is the system’s wireless communications portal. DNP3 SCADA communications allows monitoring data and reclose control commands to be exchanged between the NMS and remote WEEZAP and LYNX devices embedded in the network.