Basler BE1-25 synchronous inspection relay principle and testing

Basler BE1-25 Simultaneous Inspection Relay: A Complete Guide to Principles, Testing, and Field Applications

System Overview and Application Positioning

The BE1-25 synchronous inspection relay launched by Basler Electric is a solid-state digital synchronous detection device specially designed to verify the synchronous conditions before the circuit breaker is closed. The relay measures the phase angle between the single-phase voltage on both sides of the line and bus to determine whether the closing permission condition is met, and ensures that the condition continues to meet the preset minimum time window before outputting the closing permission signal.

The typical application scenarios of BE1-25 in the power system include:

Generator grid connection: Verify synchronization conditions before connecting the generator in parallel with the power system

System segmented circuit breaker reclosing: restoring connection between two power system sections

Fast switching scheme supervision: occasions that require fast response and phase measurement circuits to quickly return

Compared with conventional synchronous detection relays, the core advantage of BE1-25 lies in its modular functional design - by selecting different voltage monitoring options, users can make the relay have the intelligent recognition ability of "voltage/no voltage/overvoltage" status of the line and bus, thus supporting various special operating modes such as "no voltage closing" and "dead bus closing", greatly expanding the scope of application of the equipment.

Core technical specifications

2.1 Simultaneous detection function

The synchronous detection function of BE1-25 is achieved by measuring the phase angle between the single-phase voltage of the line and the bus:

Phase angle setting range: 1~99 degrees (front panel dip switch, 1 degree step)

Phase angle measurement accuracy: ± 0.5 ° or ± 5% of the set value (whichever is greater), under the conditions of 50/60Hz rated frequency, 80-135V input voltage, and 25 ℃

Full temperature setting accuracy: ± 0.5 ° or ± 5% (whichever is greater), at rated frequency and input level

Delay setting: two selectable ranges

A6 option: 0.1~9.9 seconds (x 0.1 gear) or 1~99 seconds (x 1 gear)

A7 option: 1~99 cycles (based on bus frequency)

Timing accuracy (25 ℃): maximum 25ms or 5% set value (whichever is greater)

Full temperature zone timing accuracy: ± 10ms or ± 2% (whichever is greater)

2.2 Minimum voltage detection

The voltage sensing circuit of the synchronous detection circuit ensures reliable operation when the voltage is above 80V, and does not work when the voltage is below 20V. Due to individual differences in component characteristics, some units may start within the range of 45~55V. This feature ensures that the relay will not mistakenly send a closing permission signal when the system voltage drops significantly.

2.3 Output contacts and target indication

Rated output contact value:

Resistive load: 7A continuous at 120Vac; At 250Vdc, it can connect 30A (0.2s), carry continuous current of 7A, and disconnect 0.3A

Inductive load (L/R=0.04): Breaks 0.3A at 120Vac, 125Vdc, 250Vdc

The target indicator can be selected as internal excitation type or current excitation type (requiring at least 0.2A current in the output circuit). After September 2007, the target indicator has been upgraded from an electromagnetic flipping indicator to an electronic locking LED indicator - after a power outage, the locked target status automatically recovers after the power is restored, making it easy to trace faults.

Control panel and operating components

The front panel of BE1-25 integrates all operational control and status indicator components:

Phase Angle selector (00~99): Set the maximum allowed phase angle (degrees). Setting a value of 00 will prohibit simultaneous output.

TIME DELAY selector (00~99): Set the shortest duration of the same period condition. Setting a value of 00 will prohibit simultaneous output.

TIME DELAY multiplier switch: X 0.1 gear (0.1~9.9 seconds) or X 1 gear (1~99 seconds).

SYNC indicator light (red LED): When the synchronization condition continues to reach the TIME DELAY set value, it lights up and synchronizes with the SYNC output contact closure.

POWER indicator light: Indicates that the relay power supply is working properly.

Target reset switch: Manually reset the target indicator of the latch.

PUSH-TO-ENERGIZE test button (recessed, I and J): Press with a 1/8 inch diameter non-conductive thin rod, the I button closes the SYNC output contact and auxiliary SYNC output contact, and the J button closes (optional) the voltage monitoring output contact.

The core configuration component with voltage monitoring function is located on the right internal circuit board:

MODE switches No.1 (bus) and No.2 (line): Updip=NORMAL mode, Downdip=NOT-OV mode

Deliberation switches No.1~No.5: Configure the response logic of the voltage monitor

Detailed explanation of voltage monitoring function

The voltage monitoring function of BE1-25 is a key feature that distinguishes it from similar products. By selecting different sub options of Option 2 (2-A, 2-B, 2-C, 2-R, 2-T, 2-U, 2-V), the device can obtain intelligent judgment ability for the "voltage on/off/overvoltage" status of the input voltage.