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4 ACCEPTANCE/PERIODIC TESTS
Most tests use the default settings. Any required setting changes are listed with the test procedure. For details
on performing the relay test with user-specific settings during periodic testing, see Chapter 6: FUNCTIONAL
TESTS (USER SETTINGS).
1. Tests are performed using the test mode of the LPS-D which allows viewing of the internal measuring units
and functions. The measuring units and functions are actually internal to the software. There are no indi-
vidual hardware modules that are responsible for the specific measuring functions.
The test mode selects and isolates various relaying functions and measuring units, then routes their status
to the A1 (programmable alarm 1) contact. When the particular function under test has picked up, the A1
contact closes. Target information is displayed for tests that cause tripping.
Testing can be performed with outputs disabled. The A1 contact still closes whenever a trip condition
exists, however the tripping contacts do not operate. Disabling outputs can be accomplished from the
ACTIONS menu or at the start of Relay Test mode.
Contact A1 will chatter when the unit under test is near its threshold. Do not let it continue
to chatter . Remove the test current. A single contact closure is enough to determine that
the unit picked up.
CAUTION
In tests that cause tripping, the trip target type may not match the unit being tested. For example, if a Zone
1 ground fault is being tested, Zone 2 may pick up and trip the relay before the fault is in Zone 1's charac-
teristic. The target information will reflect the Zone 2 trip, not Zone 1. Keep this in mind during the tests.
Use a continuity tester with high input impedance, such as a digital ohmmeter, to monitor the A1 contact
during relay testing.
Tripping contacts will operate while the relay is in test mode unless outputs are disabled.
2. Where appropriate, current levels are defined with two numbers as xx(yy) ; xx is the value to be used for
relays rated at 5 amperes and ( yy ) is the value to be used for 1 ampere relays.
3. One or more of the electronic current sources may not be used during a test. If the source is not used, it
must be set to zero, in addition to being disabled. Also, the currents should always be set at or near zero
whenever a current source is powered on or off.
4. The phase angles of the test sources are shown relative to phase A voltage. A positive phase angle indi-
cates the referenced quantity is leading phase A voltage. A negative phase angle indicates the referenced
quantity is lagging phase A voltage.
5. All test voltages are phase-to-ground measurements unless otherwise specified.
6. Entries at the keypad are shown as KEY, with the label of the key to be pressed. For tests that require a
setting change, the setting number is shown in parentheses next to the setting. This is performed by press-
ing the SET key, choosing the setting type (Protection or General), the group (if necessary), the setting
number ( nnnn ), and ENT. The new setting may then be entered.
Operation of Potential Transformer Fuse Failure (PTFF) will activate the Critical Alarm.
7. When testing the relay using the ALPS-Link, information will automatically appear on the display only after
the relay has tripped or to report a detected error. Relay status and test mode information will not appear.
8. At the end of testing, make sure that all settings are returned to their initial values. This can be done
through the ALPS-Link by uploading the settings to the PC before testing begins and then downloading
them back to the relay when testing has been completed. If a PC is not available, scroll through all settings
using the keypad and verify each one with the settings table in Chapter 2.
GE Power Management
LPS-D Line Protection System
4.1 OVERVIEW
4.1.5 REQUIRED SETTINGS
4.1.6 GENERAL INSTRUCTIONS
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