Siemens SIPROTEC 7SJ62 Instruction Manual page 190

Functions
67-2 Relay Element
67-1 Relay Element
67-TOC Relay
Element With IEC
Curves
6-50
panying addresses appear in the overview of setting groups only when the functions
are configured as present (Section 5.1). The functions may be enabled by selecting a
time characteristic(i.e. Definite, ANSI, or User-Defined) during configuration.
The functions associated with directional overcurrent protection were established dur-
ing configuration of protective functions (Section 5.1) at address  72&.
If address  was set to 'HILQLWH 7LPH 2QO\, then only the settings for the def-
inite-time elements are available.
At address  )&7 72&, directional phase overcurrent protection may be
switched 21 or 2)).
The pickup and delay of the 67-2 relay element are set at addresses  
3,&.83 and   '(/$< respectively. The 67-2 relay element is typically uti-
lized for protection against high magnitude faults. For this reason, the relay element
pickup is often set high while the delay is set short. It is always important to set the
pickup and delay such that operation of the 67-2 element will coordinate with other
protective equipment in the system.
In setting the pickup and delay of the 67-2 element, the same considerations apply as
did for the determining the pickup and delay of the 50-2 element in Subsection 6.2.2.1.
The delay set at address  is in addition to the 67-2 pickup time. The delay of the
67-2 element may be set to ∞. The 67-2 element will then pickup and generate a mes-
sage, but will never trip. If the 67-2 element is not required at all, then the pickup value
should be set to ∞ thus preventing pickup, trip, and the generation of a message.
The pickup value of the 67-1 relay element (set at address   3,&.83)
should be set above the maximum anticipated load current. Pickup due to overload
should never occur since the 50-1 relay element is designed only for fault protection.
For this reason, a setting equal to 120 % of the expected peak load is recommended
for line protection, and a setting equal to 140 % of the expected peak load is recom-
mended for transformers and motors.
If the 7SJ62 relay is used to protect transformers or motors with large inrush currents,
the inrush restraint feature may be used to prevent a false trip of the 67-1 relay ele-
ment. The configuration data for the inrush restraint feature is programmed at address
block 22 (see Subsection 6.5.2).
The delay of the 67-1 element is set at address   '(/$< and should be
based on system coordination requirements. The delay for directional elements is usu-
ally set shorter than the delay for non-directional elements since the non-directional
elements overlap the directional elements as backup protection.
For parallel transformers supplied from a single source (see Figure 6-19), the delay of
the directional elements located on the load side of the transformers may be set to
zero if desired.
The delay set at address  is in addition to the 67-1 pickup time. The delay of the
67-1 element may be set to ∞. The 67-1 element will then pickup and generate a mes-
sage, but will never trip. If the 67-1 element is not required at all, then the pickup value
should be set to ∞ thus preventing pickup, trip, and the generation of a message.
Pickup of the 67-TOC relay element will occur for currents greater than or equal to
110% of the 67-TOC element's pickup value, and may or may not occur for currents
between 100% and 110% of the 67-TOC element's pickup value. Dropout of the 67-
TOC relay element occurs when the current decreases to 95% of the 67-TOC ele-
ment's pickup value.
7SJ62 Manual
C53000-G1140-C121-1