Basler Electric BE1-50/51B-219 - Manual (Page 30)

24 9252000981 Rev J
Figure 9. Integrating Reset Characteristic Curve
Instantaneous Overcurrent (50) Element
Setting the INST PICKUP at the minimum pickup setting places the relay in the most sensitive state and
may be used as a safety setting.
BE1-50/51B-219 Pickup
Setting Range: 1 to 99 Aac
Setting Increment: 1 Aac
Accuracy: ±2%, ±25 milliamperes at or above 1.0 ampere setting
BE1-50/51B-226 Pickup
Setting Range: 0.2 to 19.8 Aac
Setting Increment: 0.2 Aac
Accuracy: ±2%, ±5 milliamperes at or above 0.2 ampere setting
Dropout
Dropout occurs at 95% of pickup value.
Curve Characteristics
Instantaneous characteristic curves are similar to standard electromechanical instantaneous units.
However, the time to trip for applications where the initial current through the relay is less than 0.4
ampere (5-ampere relay) or 0.08 ampere (1-ampere relay) may be slightly longer. This may occur on a
very lightly loaded circuit or when the relay is providing ground protection and is connected to measure
neutral current. Figure 10 shows the instantaneous characteristic curves for maximum time to trip.
1.0
10.0
100.0
0.000 0.200 0.400 0.600 0.800 1.000 1.200
Multiple of Pickup
x
R
D
(
S
e
c
o
n
d
s
)
P
0
0
4
6
-1
1
Vertical axis xRD (Seconds) is applicable for all curves and is derived from
multiplying the constant R for the curve selected times D (the Time Dial setting).
Specifications BE1-50/51B-219/-226