Benderr VMD423
When feeding into the public low-voltage network, voltage and frequency monitoring for network decoupling of self-generating systems > 30 kW (e.g. CHPs, wind, hydropower and photovoltaic systems) is mandatory in accordance with DIN V VDE V 0126-1-1.
The three-phase voltage and frequency monitoring relays of the VMD423 series permanently monitor the voltage and frequency in the public network at the feed. When feeding into the medium-voltage network, the output voltages and frequencies of the voltage converters (100 V) are measured. If limit values are exceeded or fallen below, they switch an alarm relay within = 80 ms (response values in accordance with the VDEW guideline 'In-house generation systems on the medium-voltage network'). An overvoltage (> U2), measured as an average over a period of 10 minutes, causes an alarm relay to switch.
The voltages are measured as effective values. In addition, asymmetry, phase failure and phase sequence are monitored.
The VMD423 is multifunctionally adjustable and can be adapted to the requirements of utility companies.
The current measured values are permanently displayed on the LC display. The measured value that causes the alarm relays to switch is saved. The requirements of the network operators can be taken into account through adjustable start-up and drop-out times, e.g. B. device-related start-up phases, short-term voltage changes, etc.
The VMD423 series requires a separate supply voltage.

• Monitoring of undervoltage, overvoltage and underfrequency and overfrequency in 3(N)AC systems AC 0.500 V
• Monitoring of overvoltage as the average of the current 10 minute measuring interval
• Monitoring of asymmetry, phase failure, phase sequence
• Start-up, response and Release delay adjustable
• Adjustable switching hysteresis
• RMS value measurement (AC + DC)
Sales unit: 1 ST.