BE1-51/27R - Human Machine Interface (Controls And Indicators)
2-3
Table 2-1. Controls and Indicators - Continued
Letter
Control or Indicator
Function or Indicator
K
PUSH-TO-ENERGIZE OUT-
PUT Pushbutton
Actuation of this function is by a thin non-conducting rod
(
do not use a screwdriver) through a hole in the front
panel. This allows the output relays to be manually
energized for testing of the external trip circuit(s).
ELEMENT targets, where supplied, are not operated by
this control.
L
TIMING Indicator
LEDs illuminate when the preset overcurrent pickup point
is reached and exceeded.
M
TIME DIAL Selector
Determines the time delay between sensing of the
overcurrent condition and the closing of the output relay.
Refer to Section 1 and Table 2-3 for curve selection
information.
N
TAP CAL Control
A single turn potentiometer provides adjustment of the
phase overcurrent pickup point between the selected tap
setting and the next lower tap setting.
O
INST 1 Control (Options 1-1
and 1-2 Only) **
A four turn potentiometer provides adjustment of the front
panel INST 1 trip setting over the range of 1 to 40 times
the selected phase time overcurrent pickup (TAP) value.
P
INST 1 NEUTRAL Control
(Options 1-1 and 1-2 Only)**
A four turn potentiometer provides adjustment of the front
panel INST 1 NEUTRAL trip setting over the range of 1 to
40 times the selected neutral time overcurrent pickup
(TAP) value.
Not
Shown
INST 2 Control (Option 1-2
Only) **
A four turn potentiometer provides adjustment of the front
panel INST 2 trip setting over the range of 1 to 40 times
the selected phase time overcurrent pickup (TAP) value.
Not
Shown
N/T (Normal/Test) Switch S1
This switch is mounted internally on the logic board.
Switch S1 provides stored built-in-test (BIT) programs
used during troubleshooting, repair, and calibration. This
switch is not used during normal relay setting or
operational testing.
LEGEND
*
The number of phases and neutral sensed by the relay is defined by the sensing input type (See the
Style Identification Chart, Figure 1-1).
**
This Instantaneous overcurrent sensing circuit detects levels that are multiples of the level selected for
the time overcurrent sensing circuit. Any change of the tap selector or calibration (CAL) controls will
cause a directly proportional change of the instantaneous overcurrent Levels.