PMM SHC-1 / SHC-1/1000 / SHC-2 CISPR-16 Voltage Probes

Overview

The PMM SHC-1, SHC-1/1000, and SHC-2 voltage probes are precision-calibrated, passive RF voltage measurement devices engineered for electromagnetic compatibility (EMC) immunity and emissions testing in accordance with CISPR 16-1-2:2023 and IEC 61000-4-6 standards. These probes operate on the principle of high-impedance voltage sampling across a defined 1500 Ω reference impedance—matching the standardized LISN (Line Impedance Stabilization Network) termination used in conducted disturbance measurements. Unlike active probes or oscilloscope-based solutions, the SHC series employs a fully passive, broadband resistive divider architecture with minimal phase distortion and negligible loading effects on the DUT (Device Under Test). This ensures traceable, repeatable amplitude response from 9 kHz to 30 MHz—a critical frequency range for radiated and conducted emission assessments in industrial, scientific, and medical (ISM) equipment certification.

Key Features

• Passive, wideband design with no external power supply required—eliminates noise coupling and DC bias drift.
• CISPR 16-1-2:2023 compliant calibration traceable to national metrology institutes (e.g., INRIM, PTB).
• Fixed 1500 Ω input impedance optimized for standard 50 Ω spectrum analyzer or EMI receiver inputs via integrated 50 Ω output termination.
• Stable attenuation values: 35 dB ± 0.5 dB (SHC-1, SHC-1/1000) and 30 dB ± 0.5 dB (SHC-2) across full operating bandwidth.
• Robust mechanical construction using non-magnetic, low-loss ceramic and PTFE dielectrics to minimize parasitic capacitance and ensure long-term stability.
• SHC-1/1000 variant rated for continuous operation up to 1 kV peak AC/DC, enabling safe measurement of high-voltage mains-borne disturbances without external attenuators or isolation transformers.

Sample Compatibility & Compliance

These probes are validated for use with commercial EMI receivers (e.g., Rohde & Schwarz ESR/EFS, Keysight N9048B), spectrum analyzers equipped with pre-compliance EMI measurement firmware, and automated test systems conforming to EN 55032, EN 55035, MIL-STD-461G, and FCC Part 15 Subpart B. Each unit is supplied with individual calibration certificates showing amplitude deviation vs. frequency (±0.3 dB typical), insertion loss, and VSWR (<1.15:1 up to 30 MHz). The SHC series meets the physical and electrical requirements for repeatable placement per CISPR 16-2-1:2017 Annex B, including defined probe-to-conductor spacing and mechanical rigidity for consistent coupling efficiency during radiated field probing near cables or PCB traces.

Software & Data Management

While the SHC probes themselves are hardware-only components, they integrate natively into industry-standard EMC test software platforms—including EMSCAN’s EMEye, Teseq’s EMC32, and NoiseKen’s NSG-3000 series controllers—via calibrated correction factor tables (.csv or .xml format). All calibration data includes full uncertainty budgets per ISO/IEC 17025:2017, supporting GLP/GMP audit readiness. For laboratories operating under FDA 21 CFR Part 11 or EU Annex 11, the probe’s static calibration records can be archived within LIMS or electronic lab notebooks with full revision control, signature traceability, and secure access logs.

Applications

• Conducted emission testing on AC/DC power lines, signal cables, and telecom ports per CISPR 32/35 and IEC 61000-6-3.
• Pre-compliance debugging of switching power supplies, motor drives, and LED lighting systems.
• Immunity verification of control circuits exposed to RF-induced voltages (IEC 61000-4-6).
• Field strength estimation near unshielded conductors using calibrated near-field voltage-to-field conversion algorithms.
• Verification of LISN performance and validation of common-mode voltage injection setups.

FAQ

What is the difference between SHC-1 and SHC-1/1000?
The SHC-1/1000 features reinforced insulation and voltage-rated components to support continuous operation at up to 1 kV peak, whereas the SHC-1 is rated for standard low-voltage EMC testing (typically ≤ 250 V RMS). Both share identical attenuation and impedance characteristics.
Can these probes be used with oscilloscopes?
Yes—but only when the oscilloscope input is configured for 50 Ω termination and supports DC-coupled, high-impedance-safe measurement modes. Calibration factors must be applied manually unless the scope’s firmware includes user-defined probe compensation tables.
Is recalibration required annually?
Per ISO/IEC 17025 and CISPR 16-1-2 recommendations, annual recalibration is advised for accredited laboratories; however, stability testing over 12 months typically shows drift < ±0.15 dB in attenuation across the band.
Do SHC probes require matching cables?
Yes—low-loss, phase-stable 50 Ω coaxial cables (e.g., Huber+Suhner Sucoflex 104) with known velocity factor and length-specific phase compensation are essential for accurate amplitude and phase coherence in swept-frequency measurements.
Are NIST-traceable calibration certificates included?
Each probe ships with a manufacturer-issued certificate traceable to INRIM (Italy); NIST-traceable equivalents are available upon request through authorized PMM calibration partners.