ABB RET670 Installation And Commissioning Manual

3 Necessary connection for three-phase metrosil set. Shown connections are applicable for both
types of three-phase plate.
4 Position of optional test switch for secondary injection into the high impedance differential IED.
5 Necessary connection for setting resistors. Shown connections are applicable for both types of
three-phase plate.
6 The factory made star point on a three-phase setting resistor set.
Shall be removed for installations with 650 and 670 series IEDs. This star
point is required for RADHA schemes only.
7 How to connect three individual phase currents for high impedance scheme to three CT inputs
in the IED.
8 Transformer input module, where the current inputs are located.
Note that the CT ratio for high impedance differential protection application
must be set as one.
• For main CTs with 1A secondary rating the following setting values shall be entered:
CTprim = 1A and CTsec = 1A
• For main CTs with 5A secondary rating the following setting values shall be entered:
CTprim = 5A and CTsec = 5A
• The parameter CTStarPoint shall be always left to the default value ToObject .
9 Three connections made in the Signal Matrix, which connect these three current inputs to the
first three input channels of the preprocessing function block (10). For high impedance
differential protection preprocessing function block in 3ms task shall be used.
10 Preprocessing block, to digitally filter the connected analogue inputs. Preprocessing block
outputs AI1, AI2 and AI3 shall be connected to three instances of 1Ph high impedance
differential protection HZPDIF function blocks, for example instance 1, 2 and 3 of HZPDIF in
the configuration tool.
Connections for 1Ph High impedance differential protection HZPDIF
Restricted earth fault protection REFPDIFis a typical application for 1Ph High
impedance differential protection HZPDIF. Typical CT connections for high
impedance based REFPDIF protection scheme are shown in figure
29.
Section 5 1MRK 504 088-UEN C
Installing the IED
56
Installation and commissioning manual

ABB RET670 Specifications

General

Rated Frequency	50/60 Hz
Inputs	Analog and binary inputs
Application	Protection of power systems
Communication Protocols	IEC 61850, DNP3, Modbus
Operating Temperature Range	-25°C to +55°C
Mounting	Rack mounted
Number of Binary Inputs	Up to 48
Number of Binary Outputs	32
Protection Functions	Overcurrent Protection
Outputs	Binary outputs
Enclosure	IP 54
Type	Line Differential Protection
Number of Analog Inputs	24