Toshiba GR200 Series Instruction Manual page 176

Hide thumbs Also See for GR200 Series:

Phase difference calculation

|V||I|cos() 0

Amplitude calculation

|l| OC pickup current

Amplitude calculation

|Vpol| Set voltage (OV-Vpol)

Figure 2.5-3 Direction determination after loss of voltage memory

If a single phase is connected to a heavy load, and the other phases are not connected to

heavy loads, the user can program separately the directional OC element such that OC will

send a trip signal only when the fault current detected is in the same direction among two

phases or more of the three-phases.

A setting and a scheme switch, as well as the non-directional OC element, provide the

settings for the directional OC element: for example, the user can set the threshold value of

the OC at stage 1 with the setting [OC1] and Forward can be set for the scheme switch [OC1-

Dir]. Setting of the sensing angle (θ) is configured by the setting [OC1-Angle] with the value of

θ set in the range of 0–180°. Figure 2.5-4 shows an example of an angle and a characteristic

Figure 2.5-4 Examples of directional characteristic angle (θ)

6F2S1915 (0.46)

directional element

GRZ200 (Soft 031 & 032)