Transform a 4-20mA Transmitter into a Visual Display Without External Power

The KOBOLD AUF Series delivers one of the industry's simplest solution for adding local display capability to existing instrumentation. This innovative loop-powered display eliminates the need for auxiliary power supplies, reducing installation costs and complexity while providing clear, reliable process visualization exactly where operators need it.

Engineered specifically for industrial environments, the AUF creates minimal system burden with only 5V voltage drop. The compact sandwich construction installs in seconds between existing EN 175301-803 Form A (DIN 43650) connectors without requiring panel cutouts, conduit runs, or electrical permits.

Why the AUF Display Outperforms Traditional Panel Meters

Unlike conventional panel displays requiring dedicated power supplies and mounting space, the AUF's plug-on design transforms installation from hours to minutes. The bright 4-digit LED display with 5/16" digit height ensures excellent visibility from wide viewing angles, while the 90-degree rotatable housing adapts to any mounting orientation without rewiring.

The dual-button interface provides intuitive programming access to scaling, decimal point positioning, and damping settings - all stored in non-volatile EEPROM memory that retains configurations for up to 10 years without power. This eliminates reconfiguration after power interruptions, reducing maintenance requirements significantly.

Sample Applications Across Industries

Process engineers specify the AUF for pressure monitoring on hydraulic systems, temperature indication on heat exchangers, flow visualization on chemical dosing pumps, and level display on storage tanks. The universal 4-20mA compatibility works seamlessly with pressure transducers, temperature transmitters, flow meters, and level sensors.

In hazardous areas, the certified AUF-2000 model enables safe pressure monitoring on offshore platforms, temperature indication in refineries, and level display in chemical storage facilities—all with full ATEX/IECEx compliance.

The optional open collector output (AUF-1001 model) adds alarm capability to basic transmitters without control system modifications. This feature enables local alarm indication and equipment shutdown capabilities directly at the measurement point, improving response times to process deviations.

The AUF-3000 model utilizes a 3-wire configuration for systems with separate signal and power loops.

The AUF-4000 model operates differently, accepting pulse inputs from sensors and converting them to a 4-20 mA output signal while displaying the process value. This model requires external 24 VDC power and can only be calibrated when factory-mounted with the sensor.

Engineered for Reliability in Demanding Environments

Built with industrial-grade PA6 GF30 plastic housing and PMMA window, the standard AUF (1000/1001/3000) withstands operating temperatures from 32°F to 140°F (-4 to 104°F for the AUF-2000 and -4 to 176°F for the AUF-4000) while maintaining IP65 protection against dust and water ingress. The intuitive diagnostic system continuously monitors device functions, displaying clear "HI" or "LO" messages for out-of-range conditions.

The 0.2% accuracy specification combined with programmable damping from 0.3 to 20 seconds provides stable, reliable readings even in applications with process fluctuations. Temperature influence remains minimal at 0.15% per 18°F, ensuring measurement accuracy across varying conditions.

Certified for Hazardous Area Applications

The AUF-2000 model provides the same reliable performance in explosive atmospheres with full ATEX and IECEx certification (II 2G Ex ib IIC T4 Gb). This intrinsically safe version operates from -4°F to 104°F and requires an intrinsically safe power supply barrier, making it ideal for oil & gas, chemical processing, and other classified locations where local indication is critical for safety.

Technical Specifications

• Display Range: -1999 to 9999 with programmable decimal point
• Accuracy: 0.2% of span ±1 digit for precise process monitoring
• Power Requirements: None - operates entirely from 4-20mA loop current (except AUF-3000/4000: 24 VDC ±20%)
• Maximum Current Load: 60 mA ensures compatibility with all transmitters
• Voltage Drop: ≤5V minimizes impact on existing loop calculations
• Update Rate: 3 measurements per second for responsive indication
• Connection Type: EN 175301-803 Form A (DIN 43650) plug and socket
• Housing Material: Orange PA6 GF30 plastic with red PMMA window (black polyamide for AUF-2000)
• Protection Rating: IP65 for reliable industrial installations
• Operating Temperature: 32°F to 140°F (0°C to 60°C) standard models; -4°F to 104°F for AUF-2000; -4 to 176°F for AUF-4000
• Storage Temperature: -22°F to 176°F (-30°C to 80°C)
• Temperature Influence: 0.15% per 18°F (10K)

Installation and Configuration

Installation requires disconnecting the existing DIN connector, inserting the AUF between connector and socket, then reconnecting - typically completed in under 60 seconds. The included longer mounting screw ensures secure attachment while maintaining proper seal integrity.

Programming utilizes two push buttons accessible after removing four Phillips screws on the display cover. Menu-driven setup allows user modification to the zero point adjustment (4mA value), span configuration (20mA value), decimal point placement, and damping selection. All parameters store automatically in EEPROM memory.

For the AUF-2000 hazardous area model, installation must follow all applicable ATEX/IECEx requirements, including proper grounding, intrinsically safe barrier installation, and documentation per local regulations.

Models for Every Application

• AUF-1000: Standard 2-wire loop-powered display for basic indication requirements
• AUF-1001: Enhanced model with PNP open collector output for alarm applications (90 mA max)
• AUF-2000: ATEX/IECEx certified 2-wire display for hazardous area installations (II 2G Ex ib IIC T4 Gb, IECEx ib IIc T4 Gb)
• AUF-3000: 3-wire configuration for systems with separate signal and power loops
• AUF-4000: Specialized pulse input model with 4-20mA output capability (can only be calibrated with factory-mounted sensor and requires external 24VDC power supply)

Hazardous Area Specifications (AUF-2000)

• Conformance: BVS 17 ATEX E 022, IECEx BVS 17.0012
• ATEX Approval: II 2G Ex ib IIC T4 Gb
• IECEx Approval: ib IIc T4 Gb
• Voltage: Ui 28 VDC
• Current: Ii 100 mA
• Power: Pi 0.9 W
• Effective Inner Capacitance: Ci negligible
• Effective Inner Inductance: Li negligible
• Housing Material: Black polyamide compound with red PMMA window
• Ambient Temperature: -4°F to 104°F (-20°C to 40°C)

Key Features

• No external power supply required or most models (loop-powered)
• Universal compatibility with any 4-20mA transmitter
• Easy plug-on installation in under 60 seconds
• Compact sandwich construction fits between existing connectors
• Bright 4-digit LED display with 5/16" digit height
• 90-degree rotatable housing for optimal viewing
• Simple two-button programming interface
• Non-volatile EEPROM memory (10-year data retention)
• Programmable scaling, decimal point, and damping
• IP65 protection rating
• Minimal 5V voltage drop for loop-powered devices
• Integrated diagnostic system with error messages
• Optional open collector output for alarms (AUF-1001)
• ATEX/IECEx certification available (AUF-2000)

Reduce Costs and Complexity Today

Eliminate expensive power supply installations, reduce wiring complexity, and provide operators with critical process visibility using the KOBOLD AUF Series. Whether you need basic indication, alarm outputs, or a display with hazardous area certification, upgrading your instrumentation has never been simpler.