ABB REF615 L User Manual

10.2 Voltage total harmonic distortion monitoring VMHAI
10.2.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Voltage total harmonic distortion
monitoring
VMHAI PQM3U PQM3V
10.2.2 Function block
GUID-CF203BDC-8C9A-442C-8D31-1AD55110469C V1 EN
Figure 410: Function block
10.2.3 Functionality
The distortion monitoring function VMHAI is used for monitoring the voltage total
harmonic distortion THD.
10.2.4 Operation principle
The function can be enabled and disabled with the Operation setting. The
corresponding parameter values are "On" and "Off".
The operation of the voltage distortion monitoring function can be described with a
module diagram. All the modules in the diagram are explained in the next sections.
Distortion
measure-
ment
Demand
calculation
BLOCK
ALARM
U_A_AB
U_B_BC
U_C_CA
GUID-615D1A8A-621A-4AFA-ABB0-C681208AE62C V1 EN
Figure 411: Functional module diagram
1YHT530004D05 D Section 10
Power quality measurement functions
615 series 769
Technical Manual

ABB REF615 L Specifications

General

Type	Feeder Protection Relay
Rated Frequency	50/60 Hz
Weight	Approx. 1.5 kg
Communication Protocols	IEC 61850, Modbus RTU, DNP3
Protection Functions	Overcurrent, Earth fault, Thermal overload, Under/Over voltage, Under/Over frequency
Enclosure	IP20