Methodical Procedure For Primary Tests Of Functions - Siemens SIPROTEC 5 Operation Manual

Commissioning
7.5 Primary Tests
NOTE
i
i
Before you perform this test, make sure that the respective system part is isolated and a switching opera-
tion can be executed safely.
Once you have activated the switching device, check the feedbacks.
²
In the menu, go to Test suite → Analog inputs and check the voltage and current inputs. The relevant
²
measurands must have the value 0 in the de-energized switch position.
Using test equipment parallel to the transformers, feed stationary test quantities and check the measured
²
values. Take note of the absolute value and phase as well as the correct phase sequence.
NOTE
i
i
If additional signals such as from a substation automation technology are coupled, perform the corre-
sponding tests (see chapter
7.5.2

Methodical Procedure for Primary Tests of Functions

The scope of primary tests depends on the type of system. To check proper system integration, various
primary tests are performed in power plant systems. The generator delivers the necessary test quantities
based on the operating mode. Please refer to the Device manual for multifunctional machine protection for
details.
The scope of inspection is much smaller in power system protection applications. It boils down to a direction
check in the broadest sense. Differential protection tends towards overfunction in the case of sensitive setting
and a wiring error. Every function can be switched in a special mode to avoid unnecessary activation of the
circuit breakers. It is ready to function but the trip command is not switched further (see Function descriptions
in the Device manual). In the desired function, switch the Mode parameter to Test. The trip signal is supplied
with a test bit. The tripping contacts in the device are not activated and hence the circuit breaker is not actu-
ated by the protection.
If you enter these settings for the differential protection, make sure that at least one overcurrent protection is
active as backup protection. Once all preliminary measures are complete, you can begin with the actual
primary test.
First check that you can produce a non-critical switch position and that you have a specific power flow.
²
The possible load current must be greater than 10 % of the rated load. Avoid a maximum load.
Switch on the circuit breaker (for example, with synchrocheck) and check the measured values.
²
In the online mode open the editor Test suite → Analog inputs and check whether the phasor values of
²
the measuring points are plausible (absolute value, phase, phase sequence).
Check the phase displacement of the current and voltage phasors with each other.
²
Check the operational measured values per function group.
²
In the Operational indications tab, check the direction indirectly via the measured values for active and
²
reactive power. If the power flow is to the protected object (for example, line) and an ohmic inductive
load is assumed, the active and reactive power must assume positive values. The order of magnitude of
the measured values determines the current load. If 2 protection devices are connected, both must show
the same value.
Click the Fund. comp./sym.comp. tab. You can verify the direction of rotation using positive-sequence
²
and negative-sequence system quantities. The negative-sequence system quantities must be 0.
If deviations arise during the tests, check the selected settings (for example, current transformer neutral
²
point, phase sequence, etc.) and the interface in a 2nd step.
102
7.4 Secondary Tests).
SIPROTEC 5, Operation, Manual
C53000-G5040-C003-7, Edition 06.2016