Siemens SIPROTEC 7UM62, Manual

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Functions
120
7UM62 Manual
C53000-G1176-C149-3
2.16.2 Setting Hints
General The forward active power protection is only effective and accessible if this function
was set within the framework of the protective function configuration (section 2.2,
address
0132
,
FORWARD POWER
=
Enabled
. Set
Disabled
if the function is not
required. The address
3201 FORWARD POWER
, serves to switch the function
ON
or
OFF
or to block only the trip command (
Block Relay
).
Pick-up Values
Time Delays The setting of the forward power protection depends on the intended purpose. For this
reason, general setting instructions are not possible. The pickup values are set in
percent of the secondary apparent power rating S
Nsec
=
√
3
⋅
U
Nsec
⋅
I
Nsec
.
Consequently, the machine power must be converted to secondary quantities:
with P
sec
secondary active power according to setting value
S
Nsec
Secondary rated power =
√3 ⋅
U
Nsec
⋅
I
Nsec
P
mach
Active power of machine according to setting value
S
N mach
Rated apparent power of machine
U
N mach
Rated voltage of machine
I
N mach
Rated current of the machine
U
N prim
Primary rated voltage of voltage transformers
I
N prim
Primary rated current of current transformers
Address
3202
serves to set the threshold of the forward power to an underrange (
Pf<
)
and address
3203
(
Pf>
) serves to set it to overrange. Addresses
3204
T-Pf< and
3205
T-Pf> serve to set the associated time delays.
In address
3206A MEAS. METHOD
the user can select whether a fast or a precise
measuring procedure must be used for the forward power calculation. In most cases,
the precise measuring procedure is preferred in the power station sector (as a rule),
whereas the fast procedure is applied for use as network decoupling.
The set times are additional time delays not including the operating times (measuring
time, drop-out time) of the protective function.
2.16.2.1 Settings of the Forward Active Power Supervision
Setting
P
sec
S
Nsec
---------------
P
mach
S
N mach
--------------------
U
N mach
U
N prim
---------------------
I
N mach
I
N prim
------------------
⋅ ⋅
= =
Addr. Setting Title Setting Options Default Setting Comments
3201 FORWARD
POWER OFF
ON
Block relay for trip com-
mands OFF Forward Power Supervision
3202 Pf< 0.5..120.0 % 9.7 % P-forw.< Supervision Pickup
3204 T-Pf< 0.00..60.00 sec;
∞
10.00 sec T-P-forw.< Time Delay
3203 Pf> 1.0..120.0 % 96.6 % P-forw.> Supervision Pickup
3205 T-Pf> 0.00..60.00 sec;
∞
10.00 sec T-P-forw.> Time Delay
3206A MEAS. METHOD Method accurate
Method fast Method accurate Method of Operation