3 Installation and Commissioning
342
7UM62 Manual
C53000-G1176-C149-3
When testing this winding, the pickup value (referred to the rated relay current) will
amount to:
Because of the odd vector group numeral, the following pickup values apply:
Wiring
It is particularly important to check the correct wiring and allocation of all device
interfaces. The test function described in section 3.3.3 for checking the binary inputs
and outputs is a useful instrument for this. For analog inputs a plausibility check can
be performed as described above under the side title “Secondary Testing”.
Functional Test
The only functional test required for protective relays is a plausibility check of the
operational measured values by means of some secondary test equipment; this is to
ensure that no damage has occurred during transit (see also side title “Secondary
Testing”).
Undervoltage
Protection
Note: In devices where the undervoltage protection function is configured and
activated, please note the following: special measures have been taken to ensure that
the device does not pick up immediately after applying the auxiliary power supply, as
a result of the measuring voltage that is not yet present at the moment of power-up.
However, the device does pick up as soon as operating state 1 (measuring quantities
exist) has been attained.
LED Indications
After tests which cause LED indications to appear, these should be reset, at least once
by each of the possible methods: the reset bottom on the front plate and via the remote
reset relay. Please note that LEDs are automatically reset when a new fault occurs,
and that you can choose whether a new annunciation is made on pickup or on output
of a trip command (parameter
Test Switches
Check the functions of all test switches that are installed for the purposes of secondary
testing and isolation of the device. Of particular importance are test switches in current
transformer circuits. Be sure these switches short-circuit the current transformers
when they are in the test mode.
I
N Transf
I
N Relay
--------------------
I
N Transf
I
N CT (primary)
---------------------------------
k
SG
IDIFF>
⋅
⋅
1316 A
1500 A
-------------------
k
VG
IDIFF>
⋅
⋅
=
=
0.877 k
VG
IDIFF >
⋅
⋅
(
)
=
I
Pickup
I
N Relay
-------------------
0.877 IDIFF >
⋅
=
Three-phase
k
VG
= 1
Two-phase
k
VG
=
√
3/2
Single-phase
k
VG
=
√
3
I
Pickup
I
N Relay
-------------------
0.760 IDIFF >
⋅
=
I
Pickup
I
N Relay
-------------------
1.52 IDIFF >
⋅
=
