Toshiba GR200 Series - 2.24.1 Drop-off and pick-up characteristic; 2.24.2 Time characteristic; (i) Definite time characteristic (DT); (i)-1 Setting pick-up operation

6F2S1914 (0.49)
GRL200 (Soft 033 & 037)
- 324 -
2.24.1 Drop-off and pick-up characteristic
Figure 2.24-1 shows the UV characteristic as hatched area with concentric circles. The pick-
up threshold voltage (PU) is represented the outer circle; the drop-off voltage point (DO) is
represented the dotted circle. The PU voltage of the UV1 element is set using [UV1]. The DO
voltage of the UV1 element is set using [UV1-DPR].
The inner circle shows the area in which the UV function is blocked when the value of
the block voltage is set for [UVBLK]. Setting [TUVBLK] is also provided so that the user can
delay blocking the UV1 and UV2 elements using the setting.
V
Pickup
Drop-off
V
o
UV block
Figure 2.24-1 UV1 element characteristic
2.24.2 Time characteristic
The UV element has the relationship between an input voltage and an operation time; the
relationship is divided into two time characteristics: (i) the definite time (DT) and (ii) the
inverse definite minimum time (IDMT).
(i) Definite time characteristic (DT)
Setting pick-up operation
The user is required to set DT for scheme switch [UV1-Timer] when the UV1 element should
operate in the DT characteristic. The UV1 element has a delay timer for the pick-up operation;
the user can set a delay time using setting [TUV1]. The user can find the delay timer in the UV
function logic. (See section 2.24.4)
Setting drop-off operation
Resetting the UV1 element is performed instantly when a voltage exceeds over the drop-off
voltage.
(ii) Inverse definite minimum time (IDMT) characteristic
To operate the IDMT characteristic in the UV1 element, set scheme switch [UV1-Timer] IDMT.