Application Guide for Basler BE1-BPR Circuit Breaker Protection Relay

Basler BE1-BPR Circuit Breaker Protection Relay: A Complete Guide to Principles, Programming, and Field Applications

Product Overview and Application Positioning

The BE1-BPR circuit breaker protection relay launched by Basler Electric is a multifunctional protection device based on microprocessor design, specifically designed for circuit breaker failure protection and reclosing control in power systems. This relay adopts a three-phase+neutral line current monitoring architecture, integrating programmable logic controller (PLC) function and instantaneous overcurrent module, providing a complete solution from circuit breaker failure detection to multiple reclosing for power plants, substations, and industrial distribution systems.

The core value of BE1-BPR is reflected in three aspects: firstly, providing pre programmed circuit breaker failure logic solutions (3 standard types and 6 enhanced types), covering the vast majority of typical application scenarios; The second is the built-in BEST logic ™ Programmable logic engine, allowing users to customize protection logic without changing hardware; The third is the integration of comprehensive circuit breaker diagnostic functions, including contact wear monitoring, overheat protection of breaking resistors, arc detection, and IRIG-B high-precision time synchronization, upgrading the protection relay from a simple fault detection device to a circuit breaker health management platform.

The difference between the standard and enhanced BE1-BPR models is that the enhanced model additionally supports COMTRADE format fault recording (12 records, each containing 20 cycles of data), contact wear accumulation (I ² t) recording, and dual range current calibration function.

Core technical specifications

2.1 Current induction and fault detection

BE1-BPR provides two CT secondary rating options of 5A and 1A, which are connected to three-phase current and neutral line current through terminals 1-8:

5A CT: Continuous rated 20Aac, 1-second rated 500Aac

1A CT: continuous rated 4Aac, 1-second rated 80Aac

Three independent fault detectors (F1, F2, F3) can be independently configured for phase current or neutral line detection, and three digital filtering methods can be selected:

Type 1 (Instantaneous RMS Filter, 1 cycle): Typical startup time of 1 cycle, exit time of 1/4 cycle. The starting range is 0.25-9.99A under 5A CT (0.05-2.00A under 1A CT), with an accuracy of ± 2% or ± 0.05A. It is suitable for high-speed circuit breaker failure logic.

Type 2 (moving average filter, programmable window 1-100 cycles): The start/stop time depends on the window size and current multiplier, and the start range is 0.05-1.00A under 5A CT (0.01-0.20A under 1A CT). Suitable for weak current detection scenarios as low as 0.05A, such as circuit breaker break flashover monitoring.

Type 3 (Three phase Instantaneous RMS Filter): The performance is the same as Type 1, but it requires the three-phase current to exceed the starting value before outputting, suitable for symmetrical fault detection.

2.2 Timer System

BE1-BPR provides six independent programmable timers (T1~T6), each of which can be configured as a delay timer or a control timer:

Delay timer (D-type): It starts timing and outputs T [n] as true when the timing ends, until the reset input is valid before resetting. Suitable for circuit breaker failure delay output.

Control Timer (Type C): After starting, T [n] immediately becomes true, and when the timer ends, it becomes false, providing a finite time window. Suitable for limiting the "opportunity window" of circuit breaker failure operation.

Delay setting range: 10~999ms (1ms step), 1~60s (0.1s step), or 1~3600 cycles (1-cycle step), with a set value of 0 to disable the timer.

2.3 Recloser function

BE1-BPR has a built-in triple closing sequence, which can be configured through LR command:

Start input (START): Start the reclosing sequence when RESET is false

Reset input (RESET): Start the reset timer and close the CLOSE output

WAIT: Pause the reclosing sequence (for external locking)

Locked input (DTL): Immediately drive to the locked state (highest priority)

The three sets of reclosing delays (TD791, TD792, TD793) can be set to 0~999ms (1ms step), 1~99s (0.1s step), or 100~600s (1s step), respectively. Setting a value of 0 will cause the coincidence to fail and enter a locked state. The reset timer (TD79R) and coincidence failure timer (TD79F) provide sequence state management.

2.4 Output contacts and target indication

OUT1~OUT5: Isolated normally open contacts, OUT1 is a high-speed output (typical action time 4ms)

ALM (OUT A): normally closed alarm contact, closed when relay loses power or diagnostic alarm occurs

Output hold function (PHOLD): After the contact is closed, it holds for 200-250ms to ensure that the trip coil is not prematurely interrupted by the relay contact

Rated resistance value of output contact: 7A continuous at 120Vac; At 250Vdc, it can connect 30A (0.2s), carry 7A continuous current, and disconnect 0.3A.

Hardware architecture and front panel operation

3.1 Hardware composition

BE1-BPR adopts a pull-out chassis structure, supporting 19 inch rack installation or vertical panel installation (compatible with Basler M1, GE M1, Westinghouse FT31/FT32 and other standard openings). When the movement is pulled out, the internal CT circuit automatically short circuits without additional operation.

Front panel components (Figure 2):

POWER indicator light (green): Power supply is normal

CLOCK indicator light (red): Real time clock not set

50PU indicator light (red): Any overcurrent start value exceeded

ALARM indicator light (red): Relay diagnosis abnormal

TARGET indicator light (red): The output relay has been activated and the target information has been locked

2-line x 16 character LCD display screen: displays target, set value, status, and diagnostic information

5-key keyboard: PROG (programming), EDIT (editing) ▶ (Right/Select), ▼ (Down/Select), RESET (Reset)

3.2 HMI Menu Navigation

The main menu branches are as follows: TARGETS → RELAY SETUP → RELAY STATION → BREAKER STATION → TIMER LOG → FAILT LOG → MAINTENANCE. The right arrow key switches to the main menu, and the down arrow key enters the sub screen.

The four step process for modifying the set value is "Access → Modify → Save → Confirm": press the PROG key to enter programming mode (if password protection is enabled, prompt for password input), and use ▶ Use the ▼ key to locate parameters, use the EDIT key to modify values, and long press the PROG key for 2 seconds to bring up SAVE CHANGES? Prompt, select Y to save.

4 BESTlogic ™ Detailed Explanation of Programmable Logic

BEST logic is the core technology that distinguishes BE1-BPR from traditional relay protection devices. It allows users to define the relationship between output and input through Boolean logic equations, and can adapt to various protection requirements without replacing hardware.

4.1 Logical Variables and Equations

Naming convention for logical variables:

Variable meaning Variable meaning

I1~I7 contact inputs 1~7 O1~O5 physical outputs 1~5

F1~F3 fault detectors 1-3 O6~O12 virtual outputs 6-12

T1~T6 timers 1~6 O13~O15 dedicated virtual outputs

OA alarm virtual output

Logical operators: AND (or adjacent variable) OR（+）、NOT（/）。 For example, the logical equation * * LO1=(F1+F2) T1 */T3 * * means that when fault detector F1 or F2 is started, timer T1 outputs true and timer T3 outputs false, output 1 is closed.

The equation is expanded internally in the form of "sum of and terms", with a maximum of 4 OR terms allowed. If more items are needed, virtual output can be used as an intermediate expression.

4.2 Pre programmed logic scheme

The standard BE1-BPR comes with three pre programmed solutions:

BFL1: Three pole trip BF logic (no input/output latch), IN3~IN5 are BFI input start timer T1, IN6~IN7 are no current BFI input start T2, F3 is used for fracture arc detection, OUT4 is arc detection output.

BFL2: Three pole+single pole trip BF logic (with output latch, controlling timer limit operation window), IN6~IN7 are used for single pole trip BFI, supervised only by phase fault detector F1.

BFL3: Enhanced Lock Version BFL2, with both BFI input and output equipped with latch function.

The enhanced version provides additional BFL1E~BFL3E, with added circuit breaker protection output (O13 → OUT3) and external fault triggering (IN7 for recording COMTRADE waveforms).

4.3 Custom Logic Programming

Typical process for customizing logic:

Copy pre programming scheme: LN=BFL1

Rename: LN=BFL1_CUSTOM

Modify the equation (such as changing 52b to 52a): LO6=/I1/I2, LO12=F3/I1

Activation: LOGIC=BFL1_CUSTOM

Save: SAVE; Y

Circuit breaker diagnostic function (enhanced)

5.1 Contact Wear Monitoring (DLOG)

Calculate the cumulative breaking loss of each phase circuit breaker based on the I ² t integration principle:

D[p] = Σ(I[p][n]^2 × t_arc)

Among them, D [p] is the accumulated breaking value of the p-th phase, I [p] [n] is the RMS current at the n-th breaking, and t_arc is the arc time. DMAX is set by the user based on the manufacturer's data of the circuit breaker (unit: ampere square second, such as 2.0E6), and the cumulative value is stored in percentage form of DMAX. When D [p] exceeds 100%, a programmable diagnostic alarm is triggered.

5.2 Overheating protection for disconnecting resistors

For high-voltage circuit breakers with closing resistors, BE1-BPR tracks the number of resistor operations (RESOPS counter). Every time a disconnection operation is recorded, the counter is incremented by 1; Automatically decrease by 1 after the set reset time. When the cumulative number of operations reaches the MAXOPS set value, the output O13 is true and can be programmed as a lockout reclosing signal (BRO).

5.3 Fracture arc detection

Using a Type 2 moving average filter to detect line charging currents as low as 0.05A - When a circuit breaker flashover occurs (such as due to lightning strikes or loss of air pressure), the continuously flowing weak line charging current can be reliably detected. Logically, F3 is in phase with the position of the circuit breaker (IN1 reversed), and after a delay confirmation, drives OUT4 to trigger the reclosing of the arc extinguishing.

5.4 Timed Diagnostic Log (TLOG)

TLOG can record up to 40 events, with each event storing the remaining time and timestamp of the timer. A typical application is "margin recording" - recording the remaining time of the circuit breaker failure timer (MARGIN value in Figure 13) after the circuit breaker is normally opened and closed. By using the PTLOG command, alarm thresholds can be set for each timer. When the margin is too small, a diagnostic alarm will be automatically triggered, prompting operation and maintenance personnel to adjust the timer setting value.

5.5 COMTRADE fault recording

The enhanced BE1-BPR supports COMTRADE format waveform recording according to IEEE C37.111-1991 standard. Each record contains 4 cycles of pre fault data and 16 cycles of post fault data, with a sampling rate of 12 points per cycle. It also records three-phase and neutral line current analog quantities and 32 digital quantities (input/output/alarm status). Up to 12 records can be stored and downloaded to a PC for analysis via serial port using FLOG and FLT commands.

Installation and wiring points

6.1 Physical Installation

BE1-BPR is compatible with multiple standard chassis openings:

19 inch rack installation (Figure 16)

Vertical panel installation (Figure 18-20), compatible with Basler M1, GE M1, Westinghouse FT31/FT32 chassis

Optional decorative panel (Basler part number 9272013100) covering the opening

6.2 Terminal Wiring

AC current input (TB1:1~8):

Terminal 1-2: Phase A, Terminal 3-4: Phase B, Terminal 5-6: Phase C, Terminal 7-8: Neutral wire

DC control circuit (TB1: 9~26):

Terminal 9-10: Power input (48/125V or 125/250V depending on model)

Terminal 15-26: 7-way contact induction input (IN1~IN7, external wet voltage must be within the power supply voltage range)

Terminal 3-14: OUT1~OUT5 and ALM output

Contact induced voltage selection jumper (JP 200~JP 2006, Figure 25):

48/125V nominal: 1-2 pin jumper (26~38V start) or 2-3 pin jumper (69~100V start)

125/250V nominal: 1-2 pin jumper (69~100V start) or 2-3 pin jumper (138~200V start)

RS-232 serial port: Front panel COM0 (DB-9 female head, DCE）， Rear COM1A (DB-9 female head, DCE）， The protocol defaults to 9600 8N1 at the factory.

RS-485 port: Rear terminal block (A/B/G), supports polling multi machine communication (hardware/software handshake needs to be disabled).

IRIG-B input: Terminal block (+/-), accepts demodulated DC level shift signal (≥ 4.5V is high level), achieving ± 1ms clock synchronization accuracy.

6.3 Grounding and Dielectric Testing

The relay housing needs to be connected to the ground with a copper wire of not less than 12AWG. Dielectric testing can be performed according to IEC 255-5/ANSI IEEE C37.90-1989: apply 1500Vac/2121Vdc between circuits and to ground for 1 minute. Please note that all output terminals and power terminals are equipped with MOV surge suppressors, and the test voltage should not exceed 300V.

Calibration and on-site testing process

7.1 A/D calibration (serial port mode)

Three phase+neutral line current input in series, connected to AC current source, relay powered on

Serial port connection, ACCESS=password for programming access

FREQ=60 (or 50) Set the system frequency

Low range calibration: 5A CT applied 10A, input CAL1=10; 1A CT applies 2A, input CAL1=2

High range calibration (enhanced only): 5A CT applied 40A, input CAL2=40; 1A CT applies 8A, input CAL2=8

SAVE； Y saves calibration data

7.2 HMI calibration method

Select low range calibration on the 4th sub screen of the maintenance menu, apply the corresponding current, and then press ▶ Press the key to start calibration, display "WORKING" and finally display "CAL OK". High range calibration is a similar operation. After completion, long press the PROG button to save.

7.3 Operational Verification Testing

Select target logic scheme (LOGIC command)

Enter CT ratio (CT command), startup value (PU command), timer delay (TD command)

Configure circuit breaker status (BKROPS), resistance monitoring (BKRRES), contact wear (BKRCON/DLOG)

Simulate fault conditions using current sources and contact inputs to verify logical correctness

Use the SHOWSET command to record the final settings, and the VER command to record version information for archiving

7.4 Output Contact Test

The OUT command can be used to test the output contact action (requires Area 1 or Area 4 password):

OUT=ENABLE Enable test mode

OUT1=1, close OUT1 for 200-250ms

OUT=Disable Test Mode

Common troubleshooting guide

Troubleshooting direction

If the POWER LED is not on, check if the voltage at power terminals 9-10 is within the nominal range; Check the voltage level corresponding to the model (48/125V or 125/250V)

CLOCK LED lights up. Set the current time and date through TIME/DATE command or HMI maintenance menu; If using IRIG-B, check the signal source

Check if the starting value of PU1~PU3 is lower than the normal operating current when the 50PU LED is constantly on; Confirm whether the CT transformation ratio (CTP/CTN) is correct; Distinguish the differences in filtering characteristics between Type1/Type2/Type3

ALARM LED lights up. Use the DIAG command to check the specific alarm source (RAM/ROM/EEPROM/ADC/power/timer, etc.); Non shielded alarm needs to be returned to the factory

The TARGET LED is on but there is no output action to confirm that the PTARGET command has been correctly programmed to output the target latch; The target information can be viewed through the TARGET command

Check the external wiring and wet voltage of BFI input (IN3~IN7) when the circuit breaker fails to operate; Confirm whether the set values of timers TD1/TD2 are too short/too long; Verify the startup value of F1/F2 fault detector

The START/RESET/WAIT/LOCKOUT logic for checking the LR command configuration for reclosing sequence anomalies; Confirm the delay settings for TD791~TD793; Verify the logical polarity of contact points 5a/52 b

Serial communication cannot establish verification of baud rate/data bits/parity/stop bits (HMI maintenance menu or COM command); Rear RS-485 polling requires ID ≠ 0 and H/E handshake disabled

IRIG-B synchronization failure confirmation signal is in demodulation level shift format; Check the+/- terminal wiring; IRIG-B does not transmit the year and requires manual setting of DATE