ABB DP840 3BSE028926R1 Pulse Input Module

The ABB DP840 (Part Number: 3BSE028926R1) is a pulse input module designed for use with ABB’s S800 I/O series, primarily in combination with the AC 800M controller. This module is engineered to handle high-speed digital pulse signals, making it well-suited for frequency, counter, and time-based measurements in advanced process automation environments.

The DP840 supports multiple operating modes, including event counting, frequency measurement, and period duration analysis. Each input channel is optically isolated, ensuring high accuracy and strong protection against electromagnetic interference (EMI). It is widely used in applications where precise input from sensors, flowmeters, or encoders is critical.

Key Features

• 4 individually isolated pulse input channels

• Supports TTL, Namur, and 24 V DC signal levels

• High-speed pulse detection with configurable debounce filtering

• Multiple operation modes: counter, frequency, period measurement

• Optical isolation between channels and system bus

• Integrated diagnostics for signal monitoring

• LED indicators per channel and module status

• Compatible with ABB AC 800M and S800 I/O family

Technical Specifications

Product Advantages

• High-Speed Signal Handling: Ideal for fast pulse applications such as rotary encoders, turbine flowmeters, or shaft position monitors.

• Flexible Compatibility: Supports multiple voltage standards, including TTL and NAMUR sensors.

• Accurate Time-Based Measurements: Enables precise process timing and speed analysis in automation systems.

• Reliable Isolation: Optical channel isolation enhances signal fidelity and system reliability.

• Modular and Scalable: Fits seamlessly into ABB’s S800 I/O architecture for distributed control systems.

• Built-in Diagnostics: Supports proactive maintenance and early fault detection for process inputs.

Industry Applications

• Power Plants: Turbine speed measurement and generator synchronization

• Oil & Gas: Flowmeter pulse counting for custody transfer and production metering

• Water & Wastewater Treatment: Pump speed, motor RPM, and flowrate acquisition

• Steel & Metals: Rolling mill speed feedback and encoder signal processing

• Pharmaceutical Manufacturing: Batch timing, process cycle counting

• Automotive & Robotics: Machine cycle monitoring, precision motion timing

Frequently Asked Questions (FAQ)

1. Q: What is the primary function of the ABB DP840?

   A: The DP840 is used for high-speed pulse input measurement such as counting, frequency analysis, and time-based calculations.

2. Q: How many pulse inputs does it support?

   A: It provides 4 individually isolated digital pulse input channels.

3. Q: What voltage levels are compatible with the inputs?

   A: TTL, NAMUR, and 24 V DC pulse signals can be accepted.

4. Q: What is the maximum frequency the module can process?

   A: Typically up to 25 kHz, with up to 50 kHz supported under optimized conditions.

5. Q: Can it measure frequency and period simultaneously?

   A: No, each channel operates in a selectable mode, but the modes are configurable.

6. Q: Does it provide channel-to-channel isolation?

   A: Yes, each channel is optically isolated from the others and from the system.

7. Q: What filtering options are available?

   A: Programmable debounce times from 1 µs to 100 ms help eliminate false triggering.

8. Q: What diagnostics are available on the DP840?

   A: Line fault detection, signal presence, and input voltage status monitoring are included.

9. Q: Can this module be hot-swapped in an S800 I/O system?

   A: Yes, when used with a suitable terminal base unit.

10. Q: Is it compatible with AC 800M controller?

    A: Absolutely. It is fully supported within the ABB 800xA and AC 800M systems.