Description

The ABB TP858 is an advanced 8-channel pulse and frequency output module engineered for ABB’s AC 800M programmable automation controller platform. Designed for applications demanding precise timing, high-speed signal generation, and functional safety, it converts digital control logic into robust, isolated pulse trains for driving actuators, simulating sensors, or testing I/O systems.

This module delivers deterministic, hardware-accelerated pulse output with microsecond-level accuracy—making it indispensable in turbine control, flow calibration, motion synchronization, and safety system validation across power, oil & gas, and industrial automation sectors.

Application Scenarios

At a European combined-cycle power plant, engineers needed to validate the integrity of emergency turbine bypass valves during scheduled outages—but lacked a reliable way to simulate high-frequency feedback signals from flow meters and speed probes. By deploying the ABB TP858. they generated realistic 50 kHz pulse trains directly from the AC 800M controller, triggering full-loop diagnostics without physical rotation. The test reduced valve validation time from 8 hours to 45 minutes per unit, while the ABB TP858’s isolated outputs prevented ground-induced noise from corrupting adjacent safety I/O—a critical advantage in SIL 2 environments.

Technical Principles and Innovative Values

Innovation Point 1: Hardware-Based Pulse Generation – Unlike software-timed outputs that suffer jitter under CPU load, the ABB TP858 uses a dedicated FPGA-based counter/timer engine. This ensures sub-microsecond timing consistency—even during communication bursts or logic scans—critical for encoder emulation or synchronized valve actuation.

Innovation Point 2: Wide Voltage Tolerance & Reverse Polarity Protection – The ABB TP858 accepts signals referenced to any potential between –30 VDC and +30 VDC, making it immune to ground shifts in large plants. This eliminates the need for external isolators in most field wiring scenarios.

Innovation Point 3: Seamless 800xA Integration – In Control Builder M, users configure frequency, duty cycle, or total pulse count via intuitive function blocks. The ABB TP858 automatically handles waveform generation, freeing CPU resources for core control tasks.

Innovation Point 4: Diagnostic Transparency – Each channel’s LED provides immediate visual feedback, while the module reports internal status (e.g., short-circuit, overtemperature) to the controller—enabling predictive maintenance and rapid troubleshooting in complex I/O networks.