2 Functions
40
7UT613/63x Manual
C53000-G1176-C160-2
Time Overcurrent
Protection for Earth
Current
There is another earth current time overcurrent protection which is independent from
the before-described zero sequence time overcurrent protection. This protection, to be
configured in address
124
DMT/IDMT Earth
, acquires the current connected to a
single-phase current measuring input. In most cases, it is the starpoint current of an
earthed starpoint (for transformers, generators, motors or shunt reactors). For this pro-
tection you may select one of the characteristic types, the same way as for the phase
time overcurrent protection, no matter which characteristic has been selected for the
latter.
Overcurrent Pro-
tection for Earth
Current 2 (Starpoint
Current)
For earth current detection in 7UT613/63x a second earth current overcurrent protec-
tion is available with which a further single-phase overcurrent protection can be rea-
lised. If, for example, a transformer YNyn0 is earthed at both starpoints, the in-flowing
earth current can be monitored in each starpoint. Naturally, both earth current over-
current protection functions can be used completely independently at different points
of your system for the detection of single-phase currents. For
DMT/IDMT Earth2
under address
138
a selection can be made from the same options independently for
the other overcurrent protection functions.
Single-phase Over-
current Protection
A single-phase definite-time overcurrent protection
DMT 1PHASE
for different user re-
quirements is available in address
127
. This protection function is very well suited e.g.
for highly sensitive tank leakage protection or high-impedance unit protection. A high-
sensitivity current input can be used for this purpose.
Asymmetrical Load
Protection
The asymmetrical load protection monitors the asymmetrical current (negative se-
quence system) in three-phase protected objects. In address
140
UNBALANCE LOAD
the trip time characteristics can be set to definite time (
Definite Time
), additionally
operate according to an IEC–characteristic (
TOC IEC
) or to an ANSI–characteristic
(
TOC ANSI
). It can also be supplemented by a thermal stage (
DT/thermal
). The
asymmetrical load protection is normally not possible in single-phase applications
(address
105
PROT. OBJECT
=
1 phase transf.
or
1ph Busbar
).
Thermal Overload
Protection
In address
142
THERM. OVERLOAD
the user can additionally choose one of the two
methods of overload detection. Note that the overload protection for single-phase
busbar protection (address
105
PROT. OBJECT
=
1ph Busbar
) is not possible. If
the overload protection is not required, set to
Disabled
. Furthermore, the following
is available:
• Overload protection with a thermal replica according to IEC 60255-8,
• Overload protection with calculation of hot-spot temperature and the aging rate ac-
cording to IEC 60354
• Overload protection using a thermal replica with ambient temperature influence
In the first case it can still be selected whether only the overtemperature in the thermal
replica, resulting from the ohmic losses in the windings of the protected object must
be detected, or whether the total temperature under consideration of the coolant or en-
vironmental temperature must be calculated.
If the coolant or environmental temperature must be taken into consideration, a RTD-
box must be connected to the device (see below), via which the coolant or environ-
mental temperature is entered into the device. In this case set address
142
THERM.
OVERLOAD
=
th repl w. sens
(thermal replica with temperature measurement).
If there is no possibility to measure the coolant or environmental temperature and to
pass to the device, address
142
THERM. OVERLOAD
=
th rep w.o. sen
(thermal
replica without temperature measurement) can be set. In this case the device calcu-
Summary of Contents for SIPROTEC 7UT613 series
Page 16: ...Contents 16 7UT613 63x Manual C53000 G1176 C160 2 Literature 631 Glossary 623 Index 633 ...
Page 30: ...1 Introduction 30 7UT613 63x Manual C53000 G1176 C160 2 ...
Page 506: ...A Appendix 506 7UT613 63x Manual C53000 G1176 C160 2 7UT633 D E ...
Page 508: ...A Appendix 508 7UT613 63x Manual C53000 G1176 C160 2 7UT633 P Q ...
Page 510: ...A Appendix 510 7UT613 63x Manual C53000 G1176 C160 2 7UT635 D E ...
Page 512: ...A Appendix 512 7UT613 63x Manual C53000 G1176 C160 2 7UT635 P Q ...
Page 515: ...A 2 Terminal Assignments 515 7UT613 63x Manual C53000 G1176 C160 2 7UT633 B ...
Page 517: ...A 2 Terminal Assignments 517 7UT613 63x Manual C53000 G1176 C160 2 7UT633 N ...
Page 519: ...A 2 Terminal Assignments 519 7UT613 63x Manual C53000 G1176 C160 2 7UT635 B ...
Page 521: ...A 2 Terminal Assignments 521 7UT613 63x Manual C53000 G1176 C160 2 7UT635 N ...
Page 622: ...A Appendix 622 7UT613 63x Manual C53000 G1176 C160 2 ...
Page 632: ...Literature 632 7UT613 63x Manual C53000 G1176 C160 2 ...
