Siemens SIPROTEC 7UT613 series Manual page 252

2 Functions
252
power of the respective side), thus under address 5112 P< fwd for undershooting of
active power and under address 5115 P> fwd for exceeding of active power.
If, however, the forward power monitoring must be set in amps secondary, the active
power must be converted to a secondary value. The settings can then be effected
under address 5111 Pf< for undershooting of active power and under address 5114
Pf> for exceeding of active power.
The latter is always the case if the forward power monitoring has been assigned to a
measuring location, and not a side of the main protected object.
The following applies to the conversion:
where
P
sec
U
Nprim
U
Nsec
I
Nprim
I
Nsec
P
prim
Example:
Transformer
(winding)
Current transformer
Voltage transformer
Switching off during P<
Connecting a parallel transformer
Parallel transformer during P> 90 % = 0.9
In case of reference setting (with reference to the sides = winding data)
Address5112 P< fwd = 0.10
Address 5115 P> fwd = 0.90
When setting in watt secondary, this has the following effect
P< =
P> =
the setting values
Address 5111 Pf< = 80 W
Address 5114 Pf> = 720 W
secondary power
primary rated voltage of the voltage transformer (inter-
linked)
secondary rated current of the voltage transformer (in-
terlinked)
primary rated current of the current transformer
secondary rated current of the current transformer
primary power
16 MVA
20 kV
500 A/5 A
20 kV/100 V
10 % = 0.1
7UT613/63x Manual
C53000-G1176-C160-2