Basler Electric BE1-51/27R - Manual (Page 59)

9137200999 Rev F 53
Time Delay Selection
Note
If Timing Type Z1, Z2, or Z3 is installed, refer to time overcurrent
curve selection to obtain the desired set of time overcurrent curves
(see the Time Overcurrent Characteristic Curves chapter). Then
proceed to Step 1, following.
If Timing Type Z1, Z2, or Z3 is not installed, determine the timing type
from the model and style number for a specific relay. Then select the
appropriate timing curve (see the Time Overcurrent Characteristic
Curves chapter). Proceed to the following, Step 1.
Step 1. Referring to the appropriate time overcurrent characteristic curve, select the desired time delay
on the front panel TIME DIAL for the anticipated input overcurrent difference (multiples-of-
pickup current) from the selected time overcurrent pickup point as follows:
(Selected Pickup Point) - (Anticipated Input Overcurrent) = Overcurrent Difference from Pickup
Step 2. Set the front panel TIME DIAL as follows:
(a) On the appropriate curve, plot upward from the multiples-of-pickup-current value until the
horizontal line opposite the desired time delay (time-in-seconds) is reached. The setting
curve nearest the plot point should then be entered on the front panel TIME DIAL.
(b) Using the timing type B3, Definite Time Curve in the Time Overcurrent Characteristic
Curves chapter as an example, if the overcurrent is expected to be 4 times the pickup point
value and time delay of 4 seconds is desired, plot upward from the point 4 on the
multiples-of-pickup-current axis until the point 4 from the time-in-seconds axis is
crossed. The curve for a setting of 52 crosses the plot point and should be entered on the
front panel TIME DIAL.
(c) For a lesser overcurrent difference from the pickup point, the time delay will be greater, so
that for a multiple of 3 times the pickup current, the time delay for the previous front panel
setting of 52 will be 5.8 seconds.
Neutral Time Delay Selection
Step 1. Use the same characteristic curve used in the previous paragraph (Time Delay Selection).
However, the multiples-of-pickup current, time-in-seconds, and the resulting front panel
NEUTRAL TIME DIAL setting can differ.
Step 2. Set the front panel NEUTRAL TIME DELAY as follows:
(a) On the appropriate curve, plot upward from the multiples-of-pickup-current value until the
horizontal line opposite the desired time delay (time-in-seconds) is reached. The setting
curve nearest the plot point should then be entered on the front panel NEUTRAL TIME
DELAY.
(b) Using the timing type B3, Definite Time Curve in the Time Overcurrent Characteristic
Curves chapter as an example, if the overcurrent is expected to be 4 times the pickup point
value and time delay of 4 seconds is desired, plot upward from the point 4 on the
multiples-of-pickup-current axis until the point 4 from the time-in-seconds axis is
crossed. The curve for a setting of 52 crosses the plot point and should be entered on the
front panel NEUTRAL TIME DIAL.
(c) For a lesser overcurrent difference from the pickup point, the time delay will be greater, so
that for a multiple of 3 times the pickup current, the time delay for the previous front panel
setting of 52 will be 5.8 seconds.
BE1-51/27R Tests and Adjustments