ABB RELION RET670 User Manual

10.2.3.3 Power supply quality
M13852-16 v1
The setting has to be well above the highest occurring "normal" voltage and below the
highest acceptable voltage, due to regulation, good practice or other agreements.
10.2.3.4
High impedance
grounded systems
M13852-19 v6
In high impedance grounded systems, ground-faults cause a voltage increase in the
non-faulty phases. Two step overvoltage protection (OV2PTOV, 59) is used to detect
such faults. The setting must be above the highest occurring "normal" voltage and
below the lowest occurring voltage during faults. A metallic single-phase ground-fault
causes the non-faulted phase voltages to increase a factor of √3.
10.2.3.5 The following settings can be done for the two step overvoltage
protection
M13852-22 v10
ConnType: Sets whether the measurement shall be phase-to-ground fundamental value,
phase-to-phase fundamental value, phase-to-ground RMS value or phase-to-phase
RMS value.
Operation: Disabled/Enabled.
VBase (given in GlobalBaseSel): Base voltage phase to phase in primary kV. This
voltage is used as reference for voltage setting. OV2PTOV (59) measures selectively
phase-to-ground voltages, or phase-to-phase voltage chosen by the setting ConnType.
The function will operate if the voltage gets lower than the set percentage of VBase.
When ConnType is set to PhN DFT or PhN RMS then the IED automatically divides set
value for VBase by √3. When ConnType is set to PhPh DFT or PhPh RMS then set
value for VBase is used. Therefore, always set VBase as rated primary phase-to-phase
ground voltage of the protected object. If phase to neutral (PhN) measurement is
selected as setting, the operation of phase-to-ground over voltage is automatically
divided by sqrt3. This means operation for phase-to-ground voltage over:
(%) ( ) / 3V VBase kV> ×
EQUATION1713 V2 EN-US (Equation 480)
and operation for phase-to-phase voltage over:
Vpickup (%) VBase(kV)> ×
EQUATION1992-ANSI V1 EN-US (Equation 481)
The below described setting parameters are identical for the two steps (n = 1 or 2).
Therefore the setting parameters are described only once.
1MRK 504 163-UUS A Section 10
Voltage protection
Transformer protection RET670 2.2 ANSI 619
Application manual

ABB RELION RET670 Specifications

General

Rated Frequency	50/60 Hz
Communication Protocols	IEC 61850, IEC 60870-5-103, DNP3
Operating Temperature Range	-25°C to +55°C
Mounting	Rack Mounting
Input Voltage	100-240 V AC
Protection Functions	Overcurrent Protection
Enclosure	IP20