Settings - Siemens siprotec 7SD5 User Manual

2 Functions
The characteristic for the load angle range has to be set in a way that is just below the
minimum expected operating voltage at the maximum expected load current. In the
range of the short-circuit angles ϕ
pickup in this area. If reactive power has to be transferred via this line, it must be
ensured that the maximum reactive current at minimum operating voltage is not within
the pickup range, i.e. the short-circuit angle range ϕ
ditions in accordance with the U/I/ϕ characteristic. An arithmetic short-circuit calcula-
tion is recommended for extensive networks.
The lower threshold angle ϕ> (address 1920) should be between the load angle and
the short-circuit angle. Therefore it must be set smaller than the line angle ϕ
(X
ceeded during load conditions. If this is the case, for instance because the reactive
power has to be transferred via this line, it must be ensured that the parameters of the
voltage-dependent segment d, that is Iphi> and Uph-e (Iphi>) or Uph-ph
(Iphi>) rule out a pickup as the result of reactive power (see above).
The upper threshold angle ϕ< (address 1921) is not critical. 100° to 120° should be
sufficient in all cases.
Angular dependence, i.e. increasing the sensitivity for a large short-circuit angle with
section d and e in the characteristic, can be limited to the forward direction (line direc-
tion) using address 1919 EFFECT ϕ. In this case, EFFECT ϕ is set to Forward. Oth-
erwise EFFECT ϕ = forward&reverse. This setting is only possible via DIGSI
"Additional Settings".
2.5.1.5

Settings

Addresses which have an appended "A" can only be changed with DIGSI, under Ad-
ditional Settings.
The table indicates region-specific presettings. Column C (configuration) indicates the
corresponding secondary nominal current of the current transformer.
Addr. Parameter
1218 T3I0 1PHAS
1501 FCT Distance
1502 Minimum Iph>
1503 3I0> Threshold
1504 3U0> Threshold
1505 3U0> COMP/ISOL.
1507A 3I0>/ Iphmax
1508 SER-COMP.
132
/R ) (approx. 10° to 20°). Subsequently, you should check that the angle is not ex-
L L
C Setting Options
0.00 .. 0.50 sec; ∞
ON
OFF
1A 0.05 .. 4.00 A
5A 0.25 .. 20.00 A
1A 0.05 .. 4.00 A
5A 0.25 .. 20.00 A
1 .. 100 V; ∞
10 .. 200 V
0.05 .. 0.30
NO
YES
it must be ensured that load current may not cause
K
. If in doubt, check the pickup con-
K
Default Setting
0.04 sec
ON
0.10 A
0.50 A
0.10 A
0.50 A
5 V
40 V
0.10
NO
= arctan
L
®
at
Comments
Delay 1ph-faults
(comp/isol. star-point)
Distance protection
Phase Current threshold
for dist. meas.
3I0 threshold for neutral
current pickup
3U0 threshold zero seq.
voltage pickup
3U0> pickup (comp/ isol.
star-point)
3I0>-pickup-stabilisation
(3I0> /Iphmax)
Series compensated line
7SD5 Manual
C53000-G1176-C169-1