Product Overview
In the evolving landscape of industrial automation, precise pulse counting and frequency measurement are critical for monitoring speed, flow, and position. The ABB DP840 pulse counter addresses these needs with eight independent channels, each configurable for pulse count or frequency measurement up to 20 kHz. This module also reads inputs as digital input signals, offering flexibility for diverse applications. Built for both single and redundant setups, the DP840 integrates seamlessly into ABB's S800 I/O system.
Technical Specifications Breakdown
The DP840 delivers reliable performance with key specifications:
- 8 independent channels: Each channel operates independently for pulse count or frequency (speed) measurement, with a maximum frequency of 20 kHz.
- Signal interfaces: Supports NAMUR, 12 V, and 24 V transducer signal levels, ensuring compatibility with various sensors.
- Advanced diagnostics: On-board self-diagnostics run cyclically, with front LEDs for fault, run, warning, and primary status, plus per-channel pulse and fault indicators.
- Power and isolation: Groupwise isolated from ground, with rated insulation voltage of 50 V and dielectric test voltage of 500 V a.c. Power dissipation is 4 W, with current consumption of 115 mA on +5 V Modulebus and variable consumption on +24 V external depending on load.
- Environmental resilience: Operating temperature range 0 to +55 °C, storage from -40 to +70 °C, and protection class IP20. CE marked with hazardous location certifications including ATEX Zone 2 and cULus for Class I Division 2.
Industry Applications
In manufacturing, the DP840 excels at monitoring conveyor belt speed or counting products on a production line. For example, in a bottling plant, each channel can track individual line speeds, while the module's 20 kHz capability handles high-speed counting. In redundant configurations, it ensures uptime in critical processes like turbine speed monitoring, where the DP840's advanced diagnostics quickly flag anomalies.
Installation & Setup Guidance
Mount the DP840 on an S800 I/O rack using compatible Module Termination Units (MTUs) such as TU810V1, TU812V1, TU814V1, TU830V1, or TU833. Connect field wiring per the signal type (NAMUR, 12 V, or 24 V) and ensure cable length does not exceed 200 meters. Configure each channel's input filter and select pulse count or frequency mode via the control system. For redundant applications, pair two modules and set the primary status accordingly.
Maintenance & Reliability
Routine inspection of the DP840 should focus on verifying LED status indicators and checking for module warnings. The module's self-diagnostics simplify troubleshooting, reducing downtime. Given its operating temperature range of 0 to +55 °C and IP20 protection, install in a clean, climate-controlled environment. For vertical mounting in compact MTUs, derate ambient temperature to 40 °C. The built-in current limiting protects sensors, extending service life.
Compatibility & Integration
The DP840 integrates with ABB's S800 I/O system and works with a wide range of MTUs including TU810, TU812, TU814, TU818, TU830, TU833, TU842, TU843, TU844, TU845, TU852, and TU854. It supports both single and redundant configurations, with keying code CF for proper alignment. The module communicates via the Modulebus, and its diagnostics are accessible through the control system.
Selection Guide & Purchasing Advice
Before ordering the ABB DP840 (article number 3BSE028926R1), verify your system's compatibility with the S800 I/O platform and required MTU. Consider whether you need single or redundant operation. For hazardous environments, confirm ATEX or cULus certification requirements. SpareTechPLC offers the DP840 with expert support to ensure you select the right module for your application. Please verify current lifecycle status and availability with SpareTechPLC before ordering.
Frequently Asked Questions
Q1: Can the DP840 measure frequency below 0.5 Hz?
No, the frequency measurement range is 0.5 Hz to 20 kHz. For lower frequencies, use pulse count mode.
Q2: What is the maximum field cable length for the DP840?
The maximum cable length is 200 meters (218 yards).
Q3: Is the DP840 suitable for intrinsically safe applications?
No, the DP840 is not intrinsically safe. It is designed for non-hazardous or Zone 2/Division 2 hazardous locations.
Q4: How do I configure the input filter on the DP840?
Each channel has a configurable input filter, set via the control system software. Refer to the module manual for filter time constants.
Q5: Can the DP840 be used with 24 V sensors?
Yes, the DP840 supports 24 V d.c. (19.2 - 32 V d.c.) signal levels, along with NAMUR and 12 V.
