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B&R X20BB57
Product Series: B&R X20 BB Series (Digital Input with Diagnostics)
Product Overview:
The X20BB57 is a 16-channel digital input module with full diagnostic capability including wire-break detection and short-circuit detection. It is the diagnostic-enhanced version of the X20BB52, designed for applications where input integrity monitoring is mandatory.
Detailed content
Key Technical Specifications:
| Parameter | Value |
|---|---|
| Number of Channels | 16 |
| 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 | ≤ 2.5 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 | Wire-break, short-circuit, overvoltage, undervoltage per channel |
Functional Features:
- 16 channels with individual wire-break detection
- Short-circuit detection on every input channel
- Overvoltage and undervoltage monitoring
- Source (PNP) and sink (NPN) compatible
- Status LEDs per channel plus diagnostic LED
Working Principle:
Each input channel incorporates a diagnostic current monitor in addition to the standard optocoupler. The module injects a small diagnostic current (approximately 1 mA) into each input line. If the wire is broken, the diagnostic current cannot return, and the module flags a wire-break fault. If a short circuit to ground or supply occurs, the current exceeds the normal range, triggering a short-circuit fault. All diagnostic data is transmitted to the PLC via the X20 bus.
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
- 16 status LEDs + diagnostic LEDs
- Module width: 15 mm (X20 standard)
Advantages & Highlights:
- Full per-channel diagnostics — wire-break, short-circuit, overvoltage, undervoltage
- Early fault detection prevents unplanned machine downtime
- Identical footprint to X20BB52 — direct drop-in replacement
- Suitable for safety-related applications where input monitoring is required
- Compliant with SIL 2 / PL c when used with appropriate safety architecture
Applicable Industries:
- Automotive manufacturing
- Safety-critical machinery (per ISO 13849)
- Semiconductor equipment
- Printing and paper industry
- Food and beverage (hygiene-critical)
- Pharmaceutical production
Installation Requirements:
- Mount on DIN rail TS 35 (EN 60715)
- Connect 24 V DC sensors with correct sourcing/sinking configuration
- Wire-break diagnostic requires a minimum load current of 1 mA — ensure sensor can sink this current
- Maintain 10 mm minimum spacing between modules
- Configure diagnostic parameters in B&R Automation Studio
Usage Precautions:
- Wire-break diagnostic adds approximately 1 mA load per channel — verify sensor compatibility
- Do not exceed 30 V DC on any input
- Short-circuit diagnostic activates within 1 ms of fault occurrence
- Test diagnostic function after installation using the built-in test feature in Automation Studio
- Operating ambient: -25°C to +70°C
