(1) Measurement of the operating zone and sensitive angle of the power directional relay
In the "Ramp Test" software module, set Uab and Ia to rated values, set the step size of the Uab phase angle, and increase or decrease the voltage phase angle to measure the boundary angles φ1 and φ2 on both sides of the operating zone. Then the sensitive angle φLM = 1/2 (φ1 + φ2).
(2) Measurement of operating power
In the "Ramp Test" software module, set the angle to the sensitive angle φLM, set Ia (or Uab) to the rated value and Uab (or Ia) to zero, set the step size for Uab (or Ia), and increase the voltage (or current). Measure the operating power.
(3) Creep test
In the "Ramp Test" software module, open the current circuit, set the initial value of Uab to zero and the step size to the rated voltage, then suddenly apply or remove the voltage. The relay contacts should not have a momentary closure.
Short-circuit the voltage circuit through a resistor, set the initial value of Ia to zero and the step size to several times the rated current, then suddenly apply or remove the current. The relay contacts should not have a momentary closure.
(4) Memory function test
In the "Ramp Test" software module, set the angle to the sensitive angle, set Ia to 0.5 times and several times the rated current, and suddenly reduce Uab from 100V to zero. The relay should operate reliably, indicating good memory function.
