1-10
BE1-51/27R - General Information
M
I
I
t
×
V
N
V
Chart 1-1. Instantaneous Response Time
Time Overcurrent Pickup
Accuracy
At voltages
nominal
±5% of front panel tap selector setting with TAP CAL control fully CW or
±7% of minimum tap whichever is greater.
At voltages < nominal
±10% of calculated pickup value or ±7% of the minimum tap whichever is
greater.
To find the effective multiple of pickup current use the formula:
Where:
M
=
Multiple of tap value current
I
=
Applied current level
I
T
=
Tap value
V
N
=
Nominal voltage
V
=
Applied voltage level
Time Overcurrent Dropout
Better than 92% of pickup level.
Ratio
Instantaneous Overcurrent
Continuously adjustable over the range of 1 to 40 times the time
Pickup Range
overcurrent pickup setting.
Instantaneous Overcurrent
±2% of pickup setting.
Measuring Accuracy
Instantaneous Overcurrent
Better than 98% of pickup level.
Dropout Ratio
Instantaneous Response
Chart 1-1 shows the typical response for the instantaneous pickup
element.
Time Delay Accuracy
±5% of the characteristic curve (Figures 1-2 through 1-70) for any com-
bination of the front panel TIME DIAL setting and the front panel TAP/TAP
CAL overcurrent pickup setting.