Basler Electric BE1-87T - Manual (Page 116)

5-20 BE1-87T Test Procedures 9171300990 Rev V
Step 7. For 50 Hz Units: Holding the 50 Hz current constant at tap value, add a 100 Hz (I
100
) current in
parallel with I
50
. Increase I
100
until the REST. TRIP LED extinguishes. The inhibit percentage is
100
100
50
× I
I
at the point where the LED extinguishes.
Expected Values: 12±3% for single-phase
18±3% for three-phase
For 60 Hz Units: Holding the 60 Hz current constant at tap value, add a 120 Hz (I
120
) current in
parallel with I
60
. Increase I
120
until the REST. TRIP LED extinguishes. The inhibit percentage is
100
120
60
× I
I
at the point where the LED extinguishes.
Expected Values: 12±3% for Single-Phase
18±3% for Three-Phase
Fifth-Harmonic Inhibit
Step 8. For 50 and 60 Hz Units: Apply tap value (1 pu) to Input 1. REST. TRIP LED should be
illuminated.
For Three- Phase Units: Return S2 to the NORMAL position.
Step 9. For 50 Hz Units: Holding the 50 Hz current constant at tap value, add a 250 Hz (I
250
) current in
parallel with I
50
. Increase I
250
until the REST. TRIP LED extinguishes. The inhibit percentage is
100
250
50
× I
I
at the point where the LED extinguishes.
Expected Values: 35±3% for single-phase or three-phase units.
For 60 Hz Units: Holding the 60 Hz current constant at tap value, add a 300 Hz (I
300
) current in
parallel with I
60
. Increase I
300
until the REST. TRIP LED extinguishes. The inhibit percentage is
100
300
60
× I
I
at the point where the LED extinguishes.
Expected Values: 35±3% for single-phase or three-phase units.
Testing Three-Phase Units without Changing Jumpers
The simplest way to test three-phase units using only two test currents is to set all jumpers to the WYE
position. Then each comparison circuit is tested independently when the respective phase currents are
applied. This is not acceptable from two points of view:
• Requires changing the relay settings (jumpers) from the in-service position.
• Does not verify that the jumpers have been properly set.
It is possible to completely test the BE1-87T with the jumpers set to the in-service position and still use
only two input current sources. When the jumpers are in the positions shown in Table 5-9, the respective
current inputs are compared.