Basler BE1-25 synchronous inspection relay principle and testing

4.1 MODE Switch - Define State Boundaries

NORMAL mode (dial up):

The low voltage threshold (set by DL/NOT OV control) is defined as "no voltage (DEAD)"

Above the high voltage threshold (set by LL/LB control) is defined as "live voltage"

Between the two is the uncertainty zone

NOT-OV mode (dial down):

Below the LIVE setting value is defined as' DEAD '(no pressure)

Between the LIVE setting value and NOT-OV setting value is defined as' LIVE '

Exceeding the NOT-OV setting value is defined as' Overvoltage '

Allow the circuit and busbar to operate in different modes, such as achieving functions such as "closing the generator circuit breaker to the dead busbar" or "prohibiting closing when the voltage is too high".

4.2 CONDITION Switch - Define Response Logic

The output conditions for configuring the voltage monitor with the ON (down) position of the five CONDITION switches are as follows:

Switch No.1 (NOT-OV enabled): When turned on, add a "non overvoltage" constraint on the LL-LB condition

Switch No.2 (LL-LB, Voltage Line/Voltage Bus): When turned on, immediately drives the voltage monitor output upon recognizing the LL-LB condition

Switch No.3 (DL-LB, no voltage line/voltage bus): When turned on, immediately drive SYNC or voltage monitoring output after identifying the condition

Switch No.4 (LL-DB, voltage line/non voltage bus): When turned on, immediately drive SYNC or voltage monitoring output after identifying the condition

Switch No.5 (DL-DB, no voltage line/no voltage bus): When turned on, immediately drive SYNC or voltage monitoring output after identifying the condition

4.3 Voltage difference monitoring (Δ V)

After selecting the voltage difference option (Option 2-A/B/C/R/T/U), BE1-25 can compare the voltage difference between the line and the bus, and prohibit synchronous output when the difference exceeds the set value, thereby reducing the system impact during closing.

Phasor Voltage Difference Detection (Option 2-R/T/U):

Calculate the vector difference between the line voltage and the bus voltage, and close the area as shown in Figure 1-2. Using the cosine theorem to calculate Δ V, the relationship is Δ V ²=VL ²+VB ² − 2 · VL · VB · cos θ. When VL is tangent to the Δ V circle, ΔV=VB·sinθ， Or θ=arcsin (Δ V/VB).

Average voltage difference detection (Option 2-A/B/C):

Detect the voltage difference of the effective value, independent of the phase angle, and the closed region is a constant Δ V boundary (Figure 1-3).

4.4 Scalable Phase Angle Window (Option 9)

In emergency situations, the phase angle window can be expanded by 2 or 3 times (determined by the position of the circuit board jumper) through external contact closure, for rapid load recovery after system failure. This option is not recommended for generator applications as excessive closing angles can generate excessive mechanical stress on the generator.

Installation and wiring points

5.1 Mechanical Installation

BE1-25 adopts the S1 standard chassis size and supports two installation methods: semi embedded or protruding. The grounding terminal at the rear of the chassis must be hard connected to the ground with a copper wire of not less than 12AWG. In multi device systems, it is recommended to lead each device separately to the grounding bus.

5.2 Wiring and connection plugs

The relay is connected to the chassis terminal through a removable connector plug (1 plug for a 10 terminal chassis, 2 plugs for a 20 terminal chassis). When unplugging, disconnect the normally open trip circuit first, short-circuit the normally closed circuit first, and then disconnect the power supply and induction circuit to ensure that the CT does not open circuit.

5.3 Contact induction configuration

BE1-25 provides two types of contact induction methods:

Isolated contact sensing (Options 1-5): The relay provides current monitoring from the internal to the external dry contacts, and no voltage should be applied externally.

Non isolated contact induction (Options 1-4): Monitor the external DC voltage source (voltage level should be the same as the relay power supply), apply voltage through contact closure to achieve signal input.

When using a T-type power supply (250Vdc or 240Vac), an external contact induction module (Figure 4-12) must be used.

5.4 Voltage Differential Resistance Module

When the mode/condition switching of the voltage monitor is controlled by external contacts (Option 2-C/U/V), a resistance module needs to be installed at the rear of the relay (Figure 4-11). When installing in a protruding manner, the module needs to be removed first, and the installation panel should be placed between the relay and the module before reinstalling.

5.5 EMI Suppression and Storage

It is recommended to parallel reverse diodes at both ends of the coil for EMI suppression in all applications where the output drive relay coil is in contact. For long-term storage (backup) equipment, it is recommended to power on and run for 30 minutes each year to extend the life of the internal aluminum electrolytic capacitor.

Complete process of on-site testing and calibration

6.1 Test Preparation