Knick P27000 Signal Conditioner Modules

Technical Dossier

Product Details And Specifications

Knick P27000 Series: Comprehensive Module Range and Technical Overview

The Knick P27000 series is a family of precision signal conditioners engineered for industrial process measurement and isolation. Manufactured in Germany by Knick Elektronische Messgeräte GmbH & Co. KG, these modules are deployed across critical infrastructure sectors including chemical processing plants, oil refineries, nuclear power facilities, and offshore platforms. The P27000 series provides galvanic isolation, signal conversion, and transmitter power supply functions that are fundamental to safe and accurate process control loops. Their compact DIN-rail form factor and wide input/output configurability have made them a standard reference component in distributed control system (DCS) and programmable logic controller (PLC) architectures globally. The series is fully compliant with NAMUR NE43 and IEC 60947 standards, and units are rated for operation in Zone 2 hazardous areas when paired with appropriate barriers.

The Evolution of P27000 Architecture

The P27000 series was introduced as part of Knick's second-generation signal conditioning platform, succeeding the earlier P10000 and P20000 families. Early P27000 variants were designed around analog isolation amplifier technology with fixed input/output ranges, targeting 4–20 mA current loop and ±10 V voltage signal conversion. As industrial automation evolved through the 1990s and 2000s, Knick expanded the P27000 catalog to include HART-transparent variants, enabling pass-through communication for smart field devices without signal degradation. The H1 suffix designation (as in P27000-H1) denotes the first hardware revision of the base module, optimized for standard 4–20 mA input with 4–20 mA isolated output and integrated transmitter power supply. Later revisions introduced wider supply voltage tolerance (19.2–31.2 V DC), improved EMC shielding to EN 61000-4, and extended temperature ratings down to –20 °C for outdoor cabinet installations. The P27000 series is now in its mature lifecycle phase. Knick continues to supply spare units and provides cross-reference compatibility with its successor Stratos and ProLine series for new installations, but the P27000 remains the dominant installed base in legacy DCS environments where form-factor and wiring compatibility are non-negotiable constraints.

P27000 Full Catalog & Functionalities (SKU List)

The following SKUs represent the verified active and legacy catalog of the Knick P27000 signal conditioner series, classified by functional category. Each model is a discrete, independently orderable unit.

Current Input / Output Isolators (4–20 mA)

• P27000-H1: 4–20 mA input to 4–20 mA isolated output, integrated 24 V transmitter supply, DIN rail mount, standard revision.
• P27000-H2: 4–20 mA input to 4–20 mA isolated output, extended supply range 19.2–31.2 V DC, enhanced EMC rating.
• P27000-H3: 4–20 mA input to 4–20 mA isolated output, HART signal transparency, bidirectional HART pass-through.
• P27000-H4: 4–20 mA input to 4–20 mA isolated output, dual-channel configuration, single DIN rail slot.

Voltage Input / Current Output Converters

• P27000-V1: ±10 V / 0–10 V input to 4–20 mA isolated output, configurable input range via DIP switch.
• P27000-V2: 0–5 V / 1–5 V input to 4–20 mA isolated output, high-impedance input stage, 100 kΩ nominal.
• P27000-V3: ±10 V input to ±10 V isolated output, voltage-to-voltage isolation amplifier, unity gain.

Thermocouple & RTD Input Modules

• P27000-T1: Thermocouple input (Type J/K/T/E/N/S/R/B selectable) to 4–20 mA isolated output, cold junction compensation integrated.
• P27000-T2: RTD input (Pt100/Pt1000, 2/3/4-wire) to 4–20 mA isolated output, linearization on-board.
• P27000-T3: Thermocouple input with HART output, compatible with HART 5/6/7 host systems.

Frequency / Pulse Input Modules

• P27000-F1: Frequency input 0–10 kHz to 4–20 mA isolated output, flow meter interface, configurable scaling.
• P27000-F2: Pulse/frequency input with totalizer function, 0–50 kHz range, NPN/PNP compatible.

Transmitter Power Supply / Loop Isolators

• P27000-S1: 2-wire transmitter power supply and loop isolator, 24 V DC loop supply, 4–20 mA pass-through isolation.
• P27000-S2: 3-wire transmitter power supply isolator, active output, short-circuit protected supply rail.
• P27000-S3: Loop-powered isolator, no external supply required, 4–20 mA in/out, NAMUR NE43 compliant.

Resistance / Potentiometer Input Modules

• P27000-R1: Resistance input 0–400 Ω / 0–4 kΩ to 4–20 mA isolated output, potentiometer and slidewire compatible.

Sourcing Hard-to-Find & Obsolete P27000 Parts

Quality Control for the P27000 Range

Each P27000 unit processed by DriveKNMS undergoes a structured functional verification protocol before shipment. The test sequence addresses the specific failure modes documented for this series, including isolation barrier degradation, output drift under thermal cycling, and HART modem circuit failure in H3/T3 variants. The standard test procedure includes: (1) dielectric withstand test at 500 V AC across input/output isolation barrier for 60 seconds; (2) loop calibration verification — input signal sweep from 4 mA to 20 mA with output accuracy check to ±0.1% of span; (3) transmitter supply voltage verification under load (600 Ω burden); (4) HART communication integrity check using a Fluke 710 HART calibrator for HART-capable variants; (5) thermal soak at 55 °C for 30 minutes to identify latent component failures. Units that fail any stage are quarantined and not dispatched. Test records are retained and available upon request for quality-critical procurement processes.