PMM 1008 Magnetic Field Immunity Test System

Overview

The PMM 1008 Magnetic Field Immunity Test System is a fully integrated, standards-compliant solution engineered for precise and repeatable evaluation of electronic equipment’s immunity to low-frequency magnetic fields, in strict accordance with IEC/EN 61000-4-8. This system implements the standardized current-driven square loop method—where a controlled alternating or transient current is injected into a calibrated induction coil to generate a uniform, calculable magnetic field within its aperture. The PMM 1008 comprises two core subsystems: the PMM 1008/1 programmable current generator and the PMM 1008/2 motor-assisted, height-adjustable, rotation-capable square loop antenna mounted on a mobile trolley and vertical stand. Its architecture prioritizes metrological traceability, operational safety, and test repeatability—features essential for accredited EMC laboratories conducting pre-compliance and full compliance validation under ISO/IEC 17025 requirements.

Key Features

• Programmable current generation with real-time closed-loop feedback via integrated current sensor—ensuring stable field output despite mains voltage fluctuations, cable heating, or contact resistance variations.
• Multi-level test execution: preconfigured IEC/EN 61000-4-8 immunity classes (1–5), user-defined field intensities (including X-level), and progressive ramp-up/down modes (fast/slow) for stress profiling.
• Integrated audible status indication (audible beep sequence) during active test phases—providing immediate operator feedback without requiring visual monitoring.
• Automatic calibration routine with user-configurable antenna factor input—supporting traceable field strength calculation per IEC 61000-4-8 Annex B.
• Comprehensive safety architecture: interlock-enabled operation, thermal overcurrent protection, <4 V_rms open-circuit voltage limit, and mechanical isolation of high-current paths.
• Compact, fanless generator design (28 kg net weight) with robust thermal management—suitable for benchtop deployment in shielded rooms or mobile test setups.
• RS232/RS485 interface (DB9) enabling remote control, script-based test sequencing, and integration into automated EMC test platforms compliant with IEEE 1671 or IEC 62680.

Sample Compatibility & Compliance

The PMM 1008 supports testing of EUTs up to 1.0 m × 1.0 m footprint within the coil aperture, accommodating typical industrial controllers, medical devices, automotive ECUs, and building automation modules. The 1.035 m × 1.035 m square loop delivers uniform field distribution across its central 0.8 m × 0.8 m zone per IEC 61000-4-8 Clause 6.2. Optional antenna variants—including 1.5 m², 2.0 m² square loops and a 2.6 m × 1.0 m rectangular loop—extend applicability to larger or non-symmetric EUT configurations. The system meets the essential requirements of the EU Electromagnetic Compatibility Directive 2014/30/EU (recast of 89/336/EEC) and Low Voltage Directive 2014/35/EU (recast of 73/23/EEC), and is designed to support GLP-aligned test documentation when paired with validated software tools.

Software & Data Management

While the PMM 1008 operates autonomously via front-panel controls, its RS232/RS485 interface enables seamless integration with third-party test management software (e.g., EMTest Teseq Control Suite, Keysight PathWave, or custom LabVIEW applications). All timing parameters—including continuous mode duration (1–12,000 min, ±1 min accuracy) and transient pulse width (1–5 s, ±1 s accuracy)—are programmable and logged with timestamps. The generator stores test configuration metadata (class, level, duration, ramp rate), supporting audit-ready records required under ISO/IEC 17025 clause 7.8 and FDA 21 CFR Part 11 when used with compliant software environments featuring electronic signatures and audit trails.

Applications

• Pre-compliance screening of industrial PLCs, motor drives, and power converters against magnetic field susceptibility.
• Full compliance verification for medical electrical equipment (IEC 60601-1-2) and railway signaling systems (EN 50121-3-2).
• Design validation of automotive electronic control units subjected to engine bay magnetic noise (ISO 11452-8).
• Research-grade characterization of magnetic shielding effectiveness and sensor drift under controlled field exposure.
• Education and training in electromagnetic compatibility principles, including field-source coupling mechanisms and immunity margin analysis.

FAQ

Does the PMM 1008 require external calibration certificates for ISO/IEC 17025 accreditation?
Yes—while the system includes automatic internal calibration routines, accredited laboratories must maintain periodic external calibration of the current sensor and loop geometry by a signatory laboratory under ILAC MRA, traceable to national standards (e.g., NIST, PTB, or NPL).
Can the PMM 1008 generate DC or pulsed magnetic fields?
No—the PMM 1008 is designed exclusively for AC (50/60 Hz) and damped sinusoidal transient (typically 50 Hz fundamental with 5 s max duration) waveforms per IEC/EN 61000-4-8; it does not support arbitrary waveform generation or static (DC) field application.
Is the trolley-mounted coil compatible with turntable-based EUT positioning?
Yes—the PMM 1008/2 trolley features casters with locking brakes and a vertically adjustable mast (200–2000 mm range), allowing co-location with standard 1.6 m diameter EMC turntables while maintaining coil centering and orientation stability.
What maintenance is required for long-term reliability?
Annual inspection of busbar connections, interlock circuit continuity, thermal cutoff response, and verification of antenna factor consistency using a reference field probe is recommended per PMM Technical Bulletin TB-EMC-1008-Rev.3.
How is field uniformity verified during setup?
Per IEC/EN 61000-4-8 Annex C, users perform a 3-point field mapping (center + two diagonally opposite corners) using a calibrated isotropic magnetic field probe prior to each EUT test session; the PMM 1008’s stable current regulation ensures minimal deviation between readings.