Basler Electric BE1-25A - Manual (Page 38)

then inhibited until such time as all vital voltages return to normal. (Because all settings and vital,
programming instructions are held in non-volatile memory (EEPROM), and are not erased if power is
lost.)
Microprocessor operation is monitored by the watchdog circuitry. If some transient condition has disrupted
the normal pattern of operation, the watchdog operates the alarm output, resets the microprocessor, and
initializes the program. The reset restarts the microprocessor. After the third such reset operation
(perhaps indicative of some hardware failure), the microprocessor is stopped and shuts down the entire
unit. This condition remains until operating power is disconnected, then reapplied. (An inoperative
microprocessor usually appears as a display that is frozen and probably inappropriate or meaningless.)
OUTPUTS
Again referencing Figure 3-2, the Output Drivers provide the interface required between the logic circuits
and the final outputs, which are the LED indicators and the output relays. The Breaker Close relay
provides a normally open contact. The other output relays are of the plug-in type, and are only
incorporated into the unit upon the addition of the relevant option(s). Note that these supplementary
relays provide both normally open and normally closed contacts for each function represented. (For the
terminal numbers of these contacts see Section 4, Installation.)
OPTIONS
The various options available for the BE1-25A Auto-Synchronizer Relay are described on the following
pages. Note that they are grouped into four categories: Voltage Acceptance, Voltage Matching,
Frequency Matching, and Dead Bus. Only one option from each category can be used at one time.
The basic Synchronizer may be upgraded to Automatic Synchronizer status by incorporating one of the
voltage matching options and/or one of the frequency matching options. This may be accomplished at any
time
− i.e., at original purchase or at any time thereafter.
Legend for Figure 3-3.
ADVANCE ANGLE - Number of degrees that the close breaker signal must precede
actual closure of the breaker so that the closure occurs at (or very
close to) zero degrees of phase difference
BF - Bus frequency
CLOSE BREAKER - Represent the closure of the BE1-25A output contact to provide
closing current to the breaker
DEAD BUS - A condition where the bus voltage is less than the setting of module
D1, VOLTS control
GF - Generator frequency
GV - Generator voltage
MAX SLIP - Maximum slip frequency setting
F
S
- Slip frequency
UV - Undervoltage Setting
3-4 BE1-25A Functional Description 9146600990 Rev S