KL3002 Beckhoff 2-Channel Analog Input Terminal (-10 to +10 V)

Product Overview

The KL3002 (KL3002) is a high-precision 2-channel analog input terminal from the Beckhoff Bus Terminal system. Designed to interface directly with field devices, it processes bipolar signals in the range of -10 V to +10 V. The module digitizes incoming analog voltages with a 12-bit resolution, providing the granularity required for monitoring motor speeds, valve positions, and sensor feedback in complex industrial loops. Unlike standard inputs, the KL3002 features differential inputs within a single housing, ensuring high signal integrity and noise immunity by rejecting common-mode interference—a critical factor in long-distance cabling across factory floors.

Functional Architecture & Isolation

The Beckhoff KL3002 is engineered for high-level system safety and data accuracy. The incoming analog signals are electrically isolated from the internal K-bus, protecting the higher-level automation device (such as a Bus Coupler or Embedded PC) from field-side electrical surges or ground loops. Integrated LED indicators provide real-time visual diagnostics, confirming active data exchange with the Bus Coupler. Its compact "fine granularity" design allows for a cost-effective 2-channel setup, organized with a common internal ground potential to simplify wiring while maintaining the benefits of a differential measurement circuit.

Technical Specifications

Technical FAQs

What is the advantage of a "Differential Input" on the KL3002?

A differential input measures the voltage difference between two points rather than measuring a signal against a noisy local ground. This makes the KL3002 far more resilient to electromagnetic interference (EMI) often caused by nearby high-power AC drives or heavy machinery.

How does the 12-bit resolution translate to measurement precision?

With a 12-bit resolution over a 20 V span (-10 V to +10 V), the module can distinguish between 4,096 discrete levels. This results in a measurement step of approximately 4.88 mV, providing high-fidelity tracking for most industrial control applications.

Can the KL3002 be used for single-ended signals?

While optimized for differential signals, it is possible to wire a single-ended sensor by connecting the negative input terminal to the local ground potential. However, for maximum accuracy and noise rejection, a true differential connection is recommended.

Field Engineering & Installation Guide

• Wiring Integrity: Use shielded twisted-pair (STP) cabling for all analog signals. Connect the cable shield to the designated ground terminal on the Beckhoff power contact or a separate shield bus to prevent the 12-bit conversion from being affected by external noise.

• Grounding Potential: While the two channels share a common internal ground potential, ensure that the differential voltage at the inputs does not exceed the maximum common-mode voltage limits specified in the Beckhoff technical documentation to avoid saturation or hardware damage.

• Terminal Placement: To minimize conversion errors due to temperature drift, avoid placing high-current power terminals (like those for large DC motors) immediately adjacent to the KL3002 without a standard air-gap or partition plate.

Engineering Advantages

The KL3002 stands out for its "Plug-and-Play" compatibility within the Beckhoff I/O ecosystem. Its ultra-compact form factor (measuring only 12 mm in width) allows for high-density analog signal processing in very small control cabinets. By providing 1.5 ms conversion times, it ensures that the PLC's process image is updated rapidly, supporting high-speed control loops and real-time data logging. It is a robust, reliable component for B2B industrial projects where precision, isolation, and space-saving are non-negotiable requirements.