Germany – VDE-AR-N 4105 (Low Voltage)

This section outlines the country-specific parameter settings for the ABB CM-UFD.M31 and CM-UFD.M31M grid monitoring relays, as required for compliance with the German VDE-AR-N 4105 standard for low-voltage grid connections.

These settings ensure proper integration of distributed energy resources into the public grid by adhering to the national limits for voltage, frequency, and disconnection behavior, as defined for systems connected to the low-voltage distribution network.

Germany VDE-AR-N 4105 settings for ABB CM-UFD.M31(M)
Menu	Submenu		Configuration option
Monitoring functions	Overvoltage >UAV	Monitoring	enabled
Monitoring functions	Overvoltage >UAV	Threshold value	1.1 x U_n
Monitoring functions	Overvoltage >UAV	Hysteresis	0.1 %
Monitoring functions	Overvoltage >U1	Monitoring	enabled
Monitoring functions	Overvoltage >U1	Threshold value	1.25 x U_n
Monitoring functions	Overvoltage >U1	Hysteresis	1 %
Monitoring functions	Overvoltage >U1	Tripping delay	0.1 s
Monitoring functions	Overvoltage >U2	Monitoring	disabled
Monitoring functions	Overvoltage >U2	Threshold value	0.005 x U_n
Monitoring functions	Overvoltage >U2	Hysteresis	0.1 %
Monitoring functions	Overvoltage >U2	Tripping delay	0.01 s
Monitoring functions	Undervoltage <U1	Monitoring	enabled
Monitoring functions	Undervoltage <U1	Threshold value	0.8 x U_n
Monitoring functions	Undervoltage <U1	Hysteresis	1 %
Monitoring functions	Undervoltage <U1	Tripping delay	1 s
Monitoring functions	Undervoltage <U2	Monitoring	enabled
Monitoring functions	Undervoltage <U2	Threshold value	0.45 x U_n
Monitoring functions	Undervoltage <U2	Hysteresis	1 %
Monitoring functions	Undervoltage <U2	Tripping delay	0.3 s
Monitoring functions	Overfrequency >F1	Monitoring	enabled
Monitoring functions	Overfrequency >F1	Threshold value	51.5 Hz
Monitoring functions	Overfrequency >F1	Hysteresis	0.1 Hz
Monitoring functions	Overfrequency >F1	Tripping delay	0.1 s
Monitoring functions	Overfrequency >F2	Monitoring	disabled
Monitoring functions	Overfrequency >F2	Threshold value	0.01 Hz
Monitoring functions	Overfrequency >F2	Hysteresis	0.01 Hz
Monitoring functions	Overfrequency >F2	Tripping delay	0.01 s
Monitoring functions	Underfrequency <F1	Monitoring	enabled
Monitoring functions	Underfrequency <F1	Threshold value	47.5 Hz
Monitoring functions	Underfrequency <F1	Hysteresis	0.1 Hz
Monitoring functions	Underfrequency <F1	Tripping delay	0.1 s
Monitoring functions	Underfrequency <F2	Monitoring	disabled
Monitoring functions	Underfrequency <F2	Threshold value	0.01 Hz
Monitoring functions	Underfrequency <F2	Hysteresis	0.01 Hz
Monitoring functions	Underfrequency <F2	Tripping delay	0.01 s
Monitoring functions	ROCOF Short for "Rate of Change of Frequency". In grid monitoring relays, it refers to how quickly the electrical frequency is changing over time. It's used to detect unstable grid conditions - especially during events like load shedding or generator disconnection - and can trigger protective actions if the frequency changes too rapidly.	Monitoring	disabled
Monitoring functions	ROCOF	Threshold value	0.005 Hz/s
Monitoring functions	ROCOF	Number of cycles	1
Monitoring functions	ROCOF	Tripping delay	0.01 s
Monitoring functions	ROCOF	Error time	0.01 s
Monitoring functions	Vector Shift VS	Monitoring	disabled
Monitoring functions	Vector Shift VS	Threshold value	0.1*
Monitoring functions	Vector Shift VS	Error time	0.01 s
Switch-on conditions	Switch-on delay	Switch-on delay	60 s
Switch-on conditions	Switch-on delay	Short interruption	enabled
Switch-on conditions	Voltage window	Monitoring	enabled
Switch-on conditions	Voltage window	Minimum	0.85 x U_n
Switch-on conditions	Voltage window	Maximum	1.1 x U_n
Switch-on conditions	Frequency window	Monitoring	enabled
Switch-on conditions	Frequency window	Minimum	47.5
Switch-on conditions	Frequency window	Maximum	50.1