B&R X20DC1198

Core Technical Specifications

• Encoder Channel Count: 1 independent differential encoder input channel
• Supported Signal Level: 5V TTL differential A/B/Z phase encoder signal
• Max Input Pulse Frequency: 1 MHz
• Counter Bit Depth: 32-bit signed high-speed counter register
• Capture Function: Z-phase zero index position latch, external hardware trigger position capture
• Diagnosis Function: A/B phase signal loss, short circuit, phase sequence error real-time detection
• Backplane Power Supply: 24VDC X20 X-Bus bus power supply
• Channel-Bus Isolation: Galvanic isolation 500 VAC
• Operating Temperature: -20°C ~ +60°C
• Module Width: 24mm, weight 62g, IP20 protection grade

Functional Features

1. Support differential A/B quadrature pulse 4x frequency multiplication counting, improve encoder position resolution four times without mechanical modification
2. Independent Z-phase zero mark capture function, accurate mechanical axis origin homing positioning
3. External hardware trigger latch input, capture real-time encoder position at trigger moment for synchronous cutting and positioning
4. Per-channel encoder wire break diagnosis; automatically report fault code once A/B/Z phase signal loss
5. 500V isolation between encoder field wiring and internal X20 bus, completely eliminate ground loop interference
6. Front panel LED indicators for counter running status, Z-phase trigger, wiring fault alarm
7. Microsecond-level high-speed data refresh with X20 CPU, suitable for high-speed servo closed-loop position feedback collection
8. Compatible X20TB6 / X20TB12 spring quick plug terminal blocks, fast wiring maintenance

Working Principle

1. 5V differential quadrature pulse signal from incremental servo encoder input to module A/B phase differential receiving circuit, Z-phase zero mark signal separately collected.
2. Internal high-speed FPGA chip executes 4x frequency multiplication on A/B phase pulse, accumulate pulse count into 32-bit signed counter register.
3. When Z-phase zero index pulse detected or external hardware trigger signal received, current counter value latched into independent capture register and uploaded to X20 CPU via X-Bus backplane.
4. Signal monitoring circuit continuously detect differential line voltage amplitude; if signal amplitude below threshold, judge encoder wire break and set fault flag in bus data.
5. Built-in differential signal filter suppress high-frequency interference pulse generated by motor drive to avoid false counting error.

Structure & Material Composition

• Housing: Flame retardant PA66 gray plastic mini module shell, X20 backplane locking buckle integrated molding
• Circuit Board: High-speed digital FR4 PCB, isolated differential signal receiving transformer between field and bus side
• Terminal Socket: Spring quick plug interface matched X20TB series removable terminal blocks
• Status Indicator: Small SMD LED embedded front panel for channel operation and fault state display

Installation Requirements

1. Vertical DIN rail installation on X20 backplane base station, 24mm narrow width high-density layout with other X20 I/O modules
2. Encoder signal cable must use shielded differential twisted pair wire, cable length ≤ 50m, shield single end grounded at module terminal side
3. Separate encoder signal wiring from inverter power cable, wiring spacing ≥ 30cm to prevent pulse counting interference
4. Cabinet ambient temperature controlled below 60°C; install cooling fan if high temperature continuous operation
5. Terminal spring clamp wire insertion depth ≥ 7mm to avoid poor differential signal contact

Application Scenarios

Operation & Maintenance Precautions

1. Module hot plugging under live bus power forbidden; must cut off base station 24V power supply before disassembly
2. Do not connect 24V voltage to 5V encoder signal terminals, overvoltage will permanently damage differential receiving chip
3. If counting position drift occurs, check encoder cable shielding integrity and differential wire short circuit status first
4. Avoid installing module in environment with conductive metal dust; metal dust entering terminal socket causes differential signal short circuit
5. Regularly clean terminal block dust accumulation every 3 months to maintain stable differential signal transmission