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B&R X20BC0083
Product Series: B&R X20 BC Series (Counter / High-Speed I/O)
Product Overview:
The X20BC0083 is a 3-channel counter and high-speed input module for the B&R X20 I/O system. It supports incremental encoder inputs (A/B phase), frequency measurement, and pulse counting at speeds up to 1 MHz. This module is essential for position feedback, speed measurement, and motion control applications.
Detailed content
Key Technical Specifications:
| Parameter | Value |
|---|---|
| Number of Counters | 3 |
| Counter Type | Up/Down counter, 32-bit |
| Encoder Input | A/B phase (quadrature), differential (RS-422) |
| Maximum Encoder Frequency | 1 MHz |
| Maximum Counting Frequency (Single-Phase) | 100 kHz |
| Counter Resolution | 32-bit (signed: -2,147,483,648 to +2,147,483,647) |
| Input Voltage (Encoder) | 5 V DC differential (RS-422 compliant) |
| Input Voltage (Digital) | 24 V DC |
| Isolation | 500 V DC (channel-to-channel, channel-to-bus) |
| Supply Voltage | 24 V DC (±20%) |
| Power Consumption | ≤ 2.0 W |
| Operating Temperature | -25°C to +70°C |
| Protection Class | IP20 (front), IP65 (with housing) |
| Dimensions (W x H x D) | 90 mm x 120 mm x 74.5 mm |
| Weight | Approximately 210 g |
| Connection | Screw terminal, 2.5 mm² |
| Diagnostics | Signal loss, overflow, underflow detection |
Functional Features:
- 3 independent 32-bit counters
- Quadrature encoder interface (A/B/Z phase support)
- Frequency measurement mode up to 1 MHz
- Gate input for time-gated counting
- Comparison output for setpoint triggering
- Zero mark (Z phase) processing for absolute position reference
- Overflow and underflow detection with interrupt capability
Working Principle:
The module contains 3 independent hardware counters, each with a 32-bit accumulator. For encoder inputs, the module decodes A/B quadrature signals to determine direction and count pulses. The Z (zero mark) signal resets or references the counter position. For single-phase pulse counting, the module counts rising and/or falling edges. The counter values are read by the PLC via the X20 bus at high speed using DMA (Direct Memory Access) for minimal CPU load.
Material Composition:
- Housing: Glass-fiber reinforced polyamide (PA66-GF30), halogen-free
- Terminals: Tin-plated copper alloy
- PCB: FR-4, conformally coated
Structural Characteristics:
- DIN rail mounting (TS 35, EN 60715)
- Spring-loaded terminal connections
- Status LEDs per counter channel
- Module width: 15 mm (X20 standard)
Advantages & Highlights:
- 1 MHz encoder frequency — suitable for high-speed servo applications
- 32-bit counters prevent overflow in long-duration counting
- Hardware-based counting — zero CPU load on the PLC
- Quadrature decoding provides direction sensing without additional wiring
- Comparison output enables hardware-triggered actions
Applicable Industries:
- CNC machines and machining centers
- Robotics and motion control
- Printing and converting machines
- Textile machinery (yarn counting)
- Packaging machines (length measurement)
- Elevator and crane position control
Installation Requirements:
- Mount on DIN rail TS 35 (EN 60715)
- Use shielded twisted-pair cables for encoder connections
- Terminate encoder lines with 100–120 Ω resistors at the module end (RS-422 standard)
- Maintain 10 mm spacing between modules
- Configure counter mode in B&R Automation Studio (encoder, pulse, frequency, gate)
Usage Precautions:
- Do not exceed 1 MHz on encoder inputs
- Maximum input voltage on encoder channels: 5 V DC differential — do not apply 24 V DC
- Use proper shielded cabling to prevent EMI-induced false counts
- Verify encoder signal levels match RS-422 specification
- Ambient: -25°C to +70°C
