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B&R X20BB81
Product Series: B&R X20 BB Series (Digital Input with Diagnostics)
Product Overview:
The X20BB81 is an 8-channel digital input module with full per-channel diagnostics including wire-break detection and short-circuit detection. It is the diagnostic variant of the X20BB80, delivering the same channel count with enhanced fault monitoring.
Detailed content
Key Technical Specifications:
| Parameter | Value |
|---|---|
| Number of Channels | 8 |
| Input Type | Digital (24 V DC) |
| Input Voltage Range | 10 V DC to 30 V DC (logic “1”) |
| Input Current (Logic “1”) | Typical 4 mA |
| Input Current (Logic “0”) | < 1 mA |
| Isolation | Group-to-group: 500 V DC |
| Response Time (ON → OFF) | ≤ 0.2 ms (typ.) |
| Response Time (OFF → ON) | ≤ 0.2 ms (typ.) |
| Supply Voltage | 24 V DC (±20%) |
| Power Consumption | ≤ 1.8 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 190 g |
| Connection | Screw terminal, 2.5 mm² |
| Diagnostics | Wire-break, short-circuit, overvoltage, undervoltage per channel |
Functional Features:
- 8 channels with individual wire-break detection
- Per-channel short-circuit monitoring
- Overvoltage and undervoltage detection
- PNP and NPN compatible
- 8 status LEDs + diagnostic indicators
Working Principle:
Identical to X20BB57 but with 8 channels instead of 16. Each channel incorporates a diagnostic current monitor that injects approximately 1 mA into the input line. Wire-break is detected when this current does not return. Short-circuit is detected when current exceeds the normal operating range. All data is sent via the X20 bus to the PLC.
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
- 8 status LEDs + diagnostic LEDs
- Module width: 15 mm (X20 standard)
Advantages & Highlights:
- Full diagnostics on all 8 channels
- Direct replacement for X20BB80 with added diagnostic capability
- Low power consumption of ≤ 1.8 W
- Suitable for safety-related monitoring per ISO 13849
- Drop-in compatible with X20BB80 footprint
Applicable Industries:
- Safety gate monitoring
- Emergency stop circuits
- Automotive assembly lines
- Pharmaceutical batch monitoring
- Food safety interlocks
- General safety-critical automation
Installation Requirements:
- Mount on DIN rail TS 35 (EN 60715)
- Wire-break diagnostic requires ≥ 1 mA load per channel
- Maintain 10 mm spacing between modules
- Configure diagnostics in B&R Automation Studio
Usage Precautions:
- Verify sensor can sink 1 mA diagnostic current
- Do not exceed 30 V DC per input
- Test all diagnostic functions post-installation
- Ambient: -25°C to +70°C
