9137200997 Rev D
BE1-51 Functional Description
3-3
If option 3 is present, an auxiliary output relay (with either N.O., N.C., or SPDT contacts) is also actuated
when the timed output relay energizes.
Instantaneous Overcurrent (Options 1-1 and 1-2)
Input current levels applied to the time overcurrent circuitry are also passed to the instantaneous
overcurrent circuitry. These levels are compared to the setting of the front panel
INST 1
adjust and the
front panel
INST 1 (NEUTRAL)
adjust (if present). If the input current level is above the setting, the output
driver energizes the instantaneous 1 output relay. If the instantaneous 2 option is present, the input level
is also compared with the setting of the front panel
INST 2
adjust to energize the instantaneous 2 output
relay. Not that the current level settings for the instantaneous overcurrent element will always be from 1 to
40 times above the front panel
TAP
and
TAP (NEUTRAL)
settings of the time overcurrent element.
If target type A or B is present, the front panel
INST 1
target and the front panel
INST 2
targets are
tripped when their respective output relay is energized, along with the front panel
A, B, C
or
N ELEMENT
targets (if present) associated with the detected phases. (See Section 2,
Controls and Indicators,
for the
types of targets that can be present depending upon the relay configuration.)
Timed and Instantaneous Outputs
Each output signal (representing either time overcurrent or instantaneous overcurrent) from each
monitored phase (or neutral) is applied to the respective output driver. Each output driver supplies
operating current to energize the associated output relay. Either normally open (output type E) or
normally closed (output type G) contacts may be specified. (The contact configurations of all output relays
for a given model will be the same.)
Auxiliary Outputs
In addition to the output relays, an auxiliary relay, having the same or a different contact configuration,
may be specified. Both the output and the auxiliary relays will remain energized for the duration of the
overcurrent condition.
Push-to-Energize Pushbuttons
If either option 2-C or 2-E is present, each individual output relay can be directly energized for test
purposes by the actuation of a front panel
PUSH-TO-ENERGIZE OUTPUT
pushbutton. The pushbutton is
actuated by the insertion of a thin, non-conducting rod through an access hole in the front panel.
Power Supply Status Output (Option 3-6)
Power supply status output relays have a set of normally closed contacts that are energized open during
power-up. If either or both power supply output legs (+12 Vdc or -12 Vdc) fails, the power supply status
output relay is de-energized and the output contacts close. Shorting bars across the output contacts are
held open by the installed connection plug. When the relay is removed from service by removing the
connection plug, the shorting bars are closed.
Target Indicators
Target indicators are optional components selected when a relay is ordered. The electronically latched
and reset targets consist of red LED indicators located on the relay front panel. A latched target is reset
by operating the target reset switch on the front panel. If relay operating power is lost, any illuminated
(latched) targets are extinguished. When relay operating power is restored, the previously latched targets
are restored to their latched state.
A relay can be equipped with either internally operated targets or current operated targets.
Internally Operated Targets
The relay trip outputs are directly applied to drive the appropriate target indicator. Each indicator is
illuminated regardless of the current level in the trip circuit.
Current Operated Targets
A current operated target is triggered by closure of the corresponding output contact and the presence of
at least 200 milliamperes of current flowing in the trip circuit.
Note that the front panel function targets (
TIMED, INST 1,
etc.) may be either internally or current
operated. Phase and neutral indicators are current operated only if the instantaneous options are not
included and if current operated targets are specified.