Table of Contents
Advertisement
1MRK 505 378-UEN Rev. K
IDiff
L
2
EQUATION1459 V1 EN-US
Phase L3:
IDiff
L3
EQUATION1460 V2 EN-US
11.3.3.1
Function revision history
Document
revision
A
B
C
D
E
F
G
H
11.3.3.2
Verifying the settings
1.
Block the trip signal from all involved IEDs with local operation released (see step 3).
2.
Set Test mode = On to test the L4CPDIF function.
3.
Release the local function with setting ReleaseLocal in local HMI under Main menu /Test /Line
differential test /LineDiffLogic
4.
Set the factor of the return currents to 1/(number of current IEDs = 1).
5.
Inject a current in phase L1, and increase the current until L4CPDIF operates for phases L1
and L2. The injected operate current must correspond to the set IdMin. The service values for
IDiffL1, IBiasL1, IDiffL2 and IBiasL2 must be equal to the injected current.
6.
Repeat the current injection in phases L2 and L3.
7.
Inject a symmetrical three-phase current, and increase the current until operation is achieved in
all three phases. The injected operate current must correspond to the set IdMin. The service
values for IDiffL1, IBiasL1, IDiffL2, IBiasL2, IDiffL3 and IBiasL3 must be equal to the injected
current.
8.
Read the transmission delay.
9.
Measure the operate time by injecting a single-phase current in phase L1. The injected current
must be 4 x the operate current. Time measurement is stopped by the trip output.
10.
Disconnect the test equipment and reconnect the current transformers.
11.
Read and check the service values of the three-phase current.
12.
Switch off the test mode and the local function.
Line differential protection RED670
Commissioning manual
=
=
× Ð
IBias
I
1 240
L
2
injected L
, 1
= IBias
= 0
L3
Product
History
revision
2.2.1
2.2.1
2.2.2
2.2.3
2.2.3
2.2.4
2.2.4
2.2.5
Tripping time in this loop test includes sending local currents to the remote end, and
sending them back. This means that tripping time is double the time achieved with
real faults or in bench testing.
With a through-load current (maximum current of line ends) of minimum 20% of
IBase, IDiff and IBias currents are read in all phases. IDiff must be less than 10% of
the maximum line end current, and IBias must be equal to the largest line end
current.
© 2017 - 2022 Hitachi Energy. All rights reserved
°
-
-
-
Added charging currents ICL1, ICL2, and ICL3 as service values
-
-
-
-
Section 11
Testing functionality by secondary injection
(Equation 2)
(Equation 3)
GUID-611723D0-41E1-4F50-B9F6-8E97948D348F v3
GUID-6C24AEF3-CD9A-4F39-A696-0125081F4892 v2
95
Advertisement
Table of Contents
