JOFRA ASC-400 Multifunction Process Calibrator

Overview

The JOFRA ASC-400 Multifunction Process Calibrator is an engineered precision instrument designed for comprehensive field and benchtop calibration of industrial process instrumentation. Built upon a robust architecture optimized for metrological integrity, the ASC-400 implements dual-channel simultaneous measurement and sourcing—enabling real-time comparison of sensor output against reference signals. Its core functionality is grounded in traceable DC voltage, current, resistance, frequency, and thermoelectric signal generation and acquisition, conforming to fundamental principles of electrical metrology and thermal transducer characterization. The device supports all standard RTD types (Pt100, Pt1000, Ni120, Cu10) and thermocouples (J, K, T, E, R, S, B, N, L, U, C), with cold-junction compensation performed internally using high-stability semiconductor sensors. Unlike basic loop calibrators, the ASC-400 integrates true-ohm resistance measurement technology—eliminating lead-wire error via 4-wire Kelvin sensing—making it suitable for high-accuracy temperature sensor verification in accordance with IEC 60751 and ASTM E230.

Key Features

• Dual independent display windows for concurrent source and readback values, enabling immediate deviation assessment without mode switching
• True-Ohm RTD measurement engine with automatic 4-wire compensation, delivering sub-0.01 Ω resolution and repeatability < ±0.02 Ω at 100 Ω
• Fuseless electronic protection across all input/output ranges, compliant with IEC 61010-1 CAT III 600 V overvoltage category
• Full-color graphical LCD with adjustable backlight and intuitive icon-based navigation—designed for readability under variable ambient lighting conditions
• Integrated cursor control and dedicated function keys for rapid access to calibration routines including % error calculation, step-and-ramp output, switch contact testing, and leak test sequencing
• Modular expansion architecture supporting external pressure modules (APM CPF series) and dry-block temperature sources—enabling full traceable calibration workflows per ISO/IEC 17025 requirements

Sample Compatibility & Compliance

The ASC-400 is compatible with a broad spectrum of industrial process sensors and transmitters, including 2-, 3-, and 4-wire RTDs; grounded, ungrounded, and exposed-junction thermocouples; 4–20 mA HART-compatible loops; and analog voltage outputs (0–10 V, ±5 V). It meets electromagnetic compatibility requirements per EN 61326-1 (industrial environment) and safety standards per EN 61010-1. When used in conjunction with accredited pressure modules (e.g., APM CPF-2000 series), calibration records satisfy traceability requirements outlined in ISO 9001, ISO/IEC 17025, and FDA 21 CFR Part 11 when paired with JOFRA’s optional calibration management software. The unit’s firmware supports audit trail logging and user-access levels—facilitating GLP/GMP-aligned documentation practices.

Software & Data Management

The ASC-400 supports bidirectional communication via USB and RS-232 interfaces, enabling integration with JOFRA’s CalDesk PC software for automated calibration procedure execution, data export (CSV, PDF), and certificate generation. CalDesk provides configurable templates aligned with ISO/IEC 17025 Annex A and NIST-traceable uncertainty budgets. All stored calibration tasks—including custom ramp profiles, tolerance limits, and pass/fail criteria—are retained in non-volatile memory with timestamping and user ID tagging. Firmware updates are delivered through signed binaries to ensure integrity and version control—critical for regulated environments requiring validation documentation.

Applications

• Verification and adjustment of temperature transmitters, controllers, and DCS I/O modules in petrochemical, pharmaceutical, and power generation facilities
• Field commissioning and periodic functional safety testing of SIL-rated temperature and pressure instrumentation per IEC 61511
• Validation of HVAC sensor networks in cleanroom environments (ISO 14644-compliant facilities)
• Supporting IQ/OQ/PQ protocols during equipment qualification in FDA-regulated manufacturing
• Technical training and metrology laboratory instruction on thermoelectric and resistive sensor behavior
• On-site troubleshooting of 4–20 mA loop integrity, including open-circuit detection, shunt verification, and HART signal injection

FAQ

Does the ASC-400 support HART communication?
No—the ASC-400 is a foundational analog calibrator and does not include native HART modulation capability. However, it can be used alongside HART communicators for physical layer verification (e.g., loop current sourcing while a separate HART tool interrogates device configuration).
Can the ASC-400 measure and source thermocouple signals simultaneously?
Yes—it features independent input and output channels, allowing concurrent thermocouple measurement (e.g., from a probe) while sourcing a different thermocouple type or value to a transmitter input.
Is the “True-Ohm” RTD measurement function calibrated to national standards?
Yes—factory calibration includes NIST-traceable resistance standards; users may perform in-house verification using certified decade resistors or send the unit to an ISO/IEC 17025-accredited lab for recalibration.
What pressure modules are compatible with the ASC-400?
Only JOFRA APM CPF-series modules (e.g., CPF-100, CPF-2000) are supported via the proprietary digital interface; third-party modules are not recognized.
Does the ASC-400 require annual recalibration?
Per ISO/IEC 17025 and manufacturer recommendations, annual calibration is advised—or more frequently if subjected to mechanical shock, extreme ambient conditions, or critical measurement applications.