Toshiba GR200 Series - (ii) Undervoltage-relay elements (UVr1, UVi1)

6F2S1914 (0.49)
GRL200 (Soft 033 & 037)
- 798 -
operating area of OV characteristic. The OVr1 element is used to check for the presence of
voltage on the running-line; similarly, the OVi1 element is used to check for the presence of
voltage on the incoming-line. The user can set pick-up thresholds using the settings [OVR1]
and [OVI1].
V
V
r
†
, V
i
‡
Pickup Voltage
0
Figure 4.6-1 Characteristics of OVr1 and OVi1
(ii) Undervoltage-relay elements (UVr1, UVi1)
Two undervoltage-relay elements (UVr1 and UVi1) are provided to determine the absence of
voltage on the running and incoming lines. In Figure 4.6-2 the hatched area depicts the
operating area of the UV characteristic. The UVr1 element is used to check for the absence of
voltage on the running-line; similarly, the UVi1 element is used to check for the absence of
voltage on the incoming-line. The user can set drop-off thresholds using the settings [UVR1]
and [UVI1].
V
V
r
†
, V
i
‡
Drop-off Voltage
0
Figure 4.6-2 Characteristics of UVr1 and UVi1
†
Note: Settings [OVR1] and [UVR1] are applied for the measurement of voltage on the
running line (Vr).
‡
Note: Settings [OVI1] and [UVI1] are applied for the measurement of voltage on the
incoming line (Vi).