Basler Electric BE1-60 - Manual (Page 18)

3-2 BE1-60 Functional Description 9170700990 Rev D
LIMIT SETTING
The limit setting is controlled by the ten-position, front-panel, Differential Limit Switch. The limit setting
circuit establishes a reference voltage that represents the maximum permissible voltage difference.
LIMIT COMPARATORS
Reference voltage established by the limit setting circuit is compared to the output of each differential
amplifier. When the limit is exceeded by the voltage difference, a limit comparator generates a trip
command signal (V > limit setting).
OUTPUTS
Limit comparator outputs are ORed so that the appropriate output relay coil energizes during a fault
condition. In a fault condition, the relay coil that energizes corresponds to the circuit that senses the lower
of the two voltage levels.
When the lower of the two voltages increases, the voltage difference decreases below the limit setting
and the relay coil de-energizes after a fixed delay of 0.75 seconds.
OUTPUT TEST PUSHBUTTONS
Two momentary-action pushbuttons, accessible through the front panel, are provided on BE1-60 relays
with a style number of X1X A1X XXCXX. The output test pushbuttons are useful for testing output relay
operation and external control/protective system wiring. The pushbuttons are operated by inserting a thin,
non-conducting rod through the appropriate front panel opening. The lower pushbutton energizes the
Circuit 1 output relay(s) and the upper pushbutton energizes the Circuit 2 output relay(s).
AUXILIARY OUTPUTS
Two sets of optional, auxiliary outputs are available on the BE1-60 relay. One auxiliary output changes
state when the Circuit 1 output relay energizes; the other auxiliary output changes state when the Circuit
2 output relay energizes. Auxiliary outputs may be specified as normally-open (style X1X A1X XXX1X),
normally-closed (style X1X A1X XXX2X), or single-pole, double-throw (SPDT) (style X1X A1X XXX3X).
POWER SUPPLY
Operating power for the relay circuitry is supplied by a wide range, electrically isolated, low-burden power
supply. Power supply operating power is not polarity sensitive. The front panel power LED and power
supply status output indicate when the power supply is operating. Power supply specifications are listed
in Table 1-1.
POWER SUPPLY STATUS OUTPUT
When the relay power supply is operating normally, the optional power supply status relay energizes and
opens the normally-closed power supply status contacts. If the power supply output falls below the proper
level or if operating power is removed from the relay, the power supply status relay de-energizes and the
power supply status output contacts close.
When the relay is equipped with a power supply status output (style X1X A1X X1XXX) and auxiliary
outputs (style X1X A1X XXX1X, X1X A1X XXX2X, or X1X A1X SSS3X), the Circuit 2 auxiliary output
contacts are dedicated as the power supply status output. The Circuit 1 auxiliary output contacts will
operate when the Circuit 1 or Circuit 2 main output contacts operate.
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.