ABB C310/0020/STD Tension Sensor Unit
Depending on the network voltage level andthe protection philosophy the following protection concepts are generally applied:
• Two main protection schemes per bay
and one busbar protection.
With REB500sys the protection concept
can be simplified. Due to the higher integration of functionality one of the main protection equipment can be eliminated.
• One main protection and one back-up
protection scheme per bay, no busbar
protection.
With REB500sys a higher availability of the
energy delivery can be reached, due to the
implementation of busbar and breaker failure protection schemes where it hasn't
been possible in the past because of economical reasons.
Nine standard options are defined for Main 2/
Group 1 or back-up bay level functions:
Line protection
- Line variant 1 (L-V1)
directional, non-directional overcurrent and
directional earth fault protection
- Line variant 2 (L-V2)
as line variant L-V1 plus distance prot.
- Line variant 3 (L-V3)
as line variant L-V2 plus autoreclosure
- Line variant 4 (L-V4)
as line variant L-V3 plus synchrocheck
- Line variant 5 (L-V5)
as line variant L-V1 plus autoreclosure and
synchrocheck.
- Line variant 6 (L-V6) for 16.7 Hz
non-directional overcurrent, distance protection, autoreclosure.
- Line variant 7 (L-V7) for 16.7 Hz
as line variant L-V6 plus directional earth
fault protection for grounded systems
Transformer protection
- Transformer variant 1 (T-V1)
2- or 3 winding transformer differential protection, thermal overload, current functions;
applicable also as autonomous T-zone protection.
- Transformer variant 2 (T-V2)
2-winding transformer differential protection, thermal overload, current functions,
overfluxing protection, neutral overcurrent
(EF).
- Transformer variant 3 (T-V3)
Distance protection for transformer back-up
or 2-winding transformer differential protection, thermal overload, current functions,
voltage functions, frequency functions,
power function, overfluxing protection.
- Transformer variant 4 (T-V4)
Transformer oriented functions/ back-up
functions -> thermal overload, current functions, voltage functions, frequency functions, power function, overfluxing protection.

There are three versions of installing the numerical busbar protection REB500 and the numeri cal station protection REB500sys:
Distributed installation
In this case, the bay units (see Fig. 24) are
installed in casings or cubicles in the indivi dual switchgear bays distributed around the
station and are connected to the central pro cessing unit by optical fiber cables. The cen tral processing unit is normally in a centrally
located cubicle or in the central relay room.
Fig. 2 Distributed installation
Centralized installation
19" mounting plates with up to three bay units
each, and the central processing unit are
mounted according to the size of the busbar
system in one or more cubicles (see Fig. 23).
A centralized installation is the ideal solution
for upgrading existing stations, since very
little additional wiring is required and com pared with older kinds of busbar protection,
much more functionality can be packed into
the same space.