Ensure that the maximum continuous current of an IED does not exceed four times its
rated value, if the measurement of the operating characteristics runs under constant
voltage conditions.
6.4.5.1
Measuring the operate limit of set values
The load encroachment function has no outputs of its own. It can only
be checked together with the impedance function.
1.
Supply the IED with healthy conditions for at least two seconds.
2.
Apply the fault condition and slowly decrease the measured impedance to find
the operate value for of the phase-to-earth and phase-to-phase loops.
6.4.5.2
Completing the test
Continue to test another function or end the testing by setting the parameter
TestMode
to
Off
under
Main menu/Tests/IED test mode/TESTMODE:1
. If another function
is tested, then set the parameter
Blocked
to
No
under
Main menu/Tests/Function test
modes/Impedance/LEPDIS/LEPDIS:1
for the function, or for each individual
function in a chain, to be tested next. Remember to set the parameter
Blocked
to
Yes
,
for each individual function that has been tested.
6.5
Testing current protection functions
6.5.1
Four step phase overcurrent protection 3-phase output
OC4PTOC
Prepare the IED for verification of settings as outlined in
.
Values of the logical signals for OC4PTOC are available on the local HMI under
Main menu/Tests/Function status/Current/OC4PTOC(51_67,4I>)/OC4PTOC:
1
. The Signal Monitoring in PCM600 shows the same signals that are available on the
local HMI.
6.5.1.1
Verifying the settings
1.
Connect the test set for current injection to the appropriate IED phases.
If there is any configuration logic that is used to enable or block any of the four
available overcurrent steps, make sure that the step under test is enabled (for
example, end fault protection).
1MRK 502 049-UEN A
Section 6
Testing functionality
59
Commissioning manual
