SEW DEH21B

SEW DEH21B

Product Introduction:
The DEH21B is a high-performance single-channel absolute encoder interface card manufactured by SEW-EURODRIVE. It is designed as an expansion option for the MOVIDRIVE MDX60B/61B series drive converters. Its primary function is to extend the drive’s capability to interface with absolute encoders via an SSI (Synchronous Serial Interface), enabling precise position feedback without the need for a reference travel at system startup. The card supports motor encoder connections via the X15 interface and absolute encoder connections via the X62 interface.

Request Quote
Category:

Description

SEW DEH21B

Technical Specifications:

  • Brand: SEW-EURODRIVE
  • Part Number: 1820 818 5
  • Type: Single-channel absolute encoder card
  • Compatible Drives: MOVIDRIVE MDX60B / MDX61B series
  • Encoder Interface: SSI (Synchronous Serial Interface) via X62 connector
  • Motor Encoder Input: X15 connector (HIPERFACE, Sin/Cos, TTL, RS422)
  • Maximum Pulse Frequency: 1 MHz
  • Counter Resolution: 16-bit programmable, 24-bit accumulator
  • Frequency Multiplication: 4x, 8x, 16x modes
  • Supply Voltage (X62): DC 24V for external encoder
  • Motor Encoder Supply (X15): DC +12V (tolerance 10.5–13V), max 650 mA
  • Operating Temperature: -25°C to +70°C
  • Installation: DIN rail or plug-in module
  • Certifications: CE, UL, CCC

Functional Features:

  • Absolute Position Feedback: Eliminates the need for reference travel at startup or after power failure, enabling immediate positioning
  • High-Speed Signal Processing: Supports up to 1 MHz pulse frequency input with hardware digital filtering (debounce time configurable from 0.1 to 10 μs)
  • Multiple Encoder Support: Compatible with HIPERFACE, Sin/Cos, TTL with negated tracks, and RS422 differential signal encoders
  • IPOS Positioning Integration: Enables free processing of absolute position data via the integrated IPOS program
  • Endless Positioning: Supports modulo function for continuous rotation applications
  • LED Status Indicators: Provides visual feedback for power, operation, error status, and channel activation
  • Photoelectric Isolation: Input isolation with common-mode rejection ratio ≥1500 Vrms

Application Scenarios:

  • Laser cutting machines requiring micron-level positioning
  • CNC grinding and milling machines
  • High-speed packaging machinery
  • Precision servo drive systems
  • Multi-axis synchronized motion control
  • High-bay warehouse positioning systems

Performance Parameters:

  • Pulse Frequency: Up to 1 MHz
  • Counter Resolution: 16-bit with 24-bit accumulator
  • Multiplication Modes: 4x, 8x, 16x
  • Digital Filter Debounce Time: 0.1–10 μs (configurable)
  • Common-Mode Rejection: ≥1500 Vrms
  • Positioning Accuracy: Dependent on encoder resolution and multiplication factor

Material Composition:

  • Industrial-grade PCB with high-density surface mount components
  • Photoelectric isolation optocouplers for signal input protection
  • Precision signal processing ICs
  • Standard DIN rail mounting bracket

Structural Features:

  • Compact plug-in module design for MOVIDRIVE MDX60B/61B expansion slots
  • X62 connector for SSI absolute encoder (9-pin: Data+, Data-, Cycle+, Cycle-, DGND, Reserved, DC 24V output)
  • X60 connector for DC 24V power supply (2-pin)
  • X15 connector for motor encoder (15-pin: Sin/Cos tracks, reference potential, temperature sensor TF/TH/KTY)
  • Anti-reverse polarity terminal protection
  • LED diagnostic indicators

Working Principle:
The DEH21B card receives raw pulse signals from an absolute or incremental encoder through the X62 or X15 interface. The internal signal processing circuit performs high-speed acquisition, frequency multiplication (4x/8x/16x), direction discrimination, and digital filtering. The processed position data is then converted into a high-resolution, low-latency digital value and transmitted to the drive controller via the internal bus interface. For SSI absolute encoders, the card initiates a synchronous serial communication sequence to read the absolute position word directly. The IPOS program within the drive can then utilize this position data for closed-loop positioning control without requiring a separate reference run.

Installation Requirements:

  • Must be plugged into a compatible MOVIDRIVE MDX60B/61B expansion slot
  • Encoder cables must use 8-core shielded twisted-pair wiring
  • Signal cables must maintain a minimum distance of 30 cm from power cables
  • Shield layer must be grounded at one end only (card side) to prevent ground loops
  • Encoder shaft alignment with motor shaft: coaxial deviation ≤0.1 mm, angular deviation ≤1.5°
  • Do not install or remove encoder connections during operation; de-energize the inverter first
  • Ambient temperature: -10°C to +50°C, relative humidity <60% RH

Usage Notes:

  • Configure encoder parameters via MOVITOOLS MotionStudio software (encoder type P090/P4.03, resolution P091/P4.04, direction P092, filter P055)
  • Verify encoder supply voltage compatibility before connection (DC 12V from X15 is sufficient for most SEW encoders except HTL types)
  • Common fault codes: F13/F013 (encoder communication error), F14/F014 (signal loss), F25/F26 (A/B/Z signal anomaly)
  • Never connect or disconnect encoder cables while the drive is energized
  • Ensure the DC 24V supply to X60 is stable within ±5% tolerance

Related products